[
  {
    "atomic_number": 1,
    "symbol": "H",
    "name": "Hydrogen",
    "atomic_mass": 1.008,
    "category": "nonmetal",
    "block": "s",
    "group_number": 1,
    "period": 1,
    "state_at_room_temp": "gas",
    "electronegativity": 2.2,
    "ionization_energy": 1312.0,
    "electron_affinity": 72.8,
    "atomic_radius": 25.0,
    "density": 8.988e-05,
    "melting_point": 14.01,
    "boiling_point": 20.28,
    "discovery_year": 1766,
    "discovered_by": "Henry Cavendish",
    "electron_configuration": "1s1",
    "electron_configuration_semantic": "1s1",
    "electrons_per_shell": [
      1
    ],
    "oxidation_states": "-1, +1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 2,
    "symbol": "He",
    "name": "Helium",
    "atomic_mass": 4.0026,
    "category": "noble_gas",
    "block": "s",
    "group_number": 18,
    "period": 1,
    "state_at_room_temp": "gas",
    "electronegativity": null,
    "ionization_energy": 2372.3,
    "electron_affinity": -48.0,
    "atomic_radius": 31.0,
    "density": 0.0001785,
    "melting_point": 0.95,
    "boiling_point": 4.22,
    "discovery_year": 1868,
    "discovered_by": "Pierre Janssen, Joseph Norman Lockyer",
    "electron_configuration": "1s2",
    "electron_configuration_semantic": "1s2",
    "electrons_per_shell": [
      2
    ],
    "oxidation_states": "0",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 3,
    "symbol": "Li",
    "name": "Lithium",
    "atomic_mass": 6.94,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 2,
    "state_at_room_temp": "solid",
    "electronegativity": 0.98,
    "ionization_energy": 520.2,
    "electron_affinity": 59.6,
    "atomic_radius": 152.0,
    "density": 0.534,
    "melting_point": 453.69,
    "boiling_point": 1615.0,
    "discovery_year": 1817,
    "discovered_by": "Johan August Arfwedson",
    "electron_configuration": "1s2 2s1",
    "electron_configuration_semantic": "[He] 2s1",
    "electrons_per_shell": [
      2,
      1
    ],
    "oxidation_states": "+1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 4,
    "symbol": "Be",
    "name": "Beryllium",
    "atomic_mass": 9.0122,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 2,
    "state_at_room_temp": "solid",
    "electronegativity": 1.57,
    "ionization_energy": 899.5,
    "electron_affinity": -48.0,
    "atomic_radius": 112.0,
    "density": 1.85,
    "melting_point": 1560.0,
    "boiling_point": 2742.0,
    "discovery_year": 1798,
    "discovered_by": "Louis Nicolas Vauquelin",
    "electron_configuration": "1s2 2s2",
    "electron_configuration_semantic": "[He] 2s2",
    "electrons_per_shell": [
      2,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 5,
    "symbol": "B",
    "name": "Boron",
    "atomic_mass": 10.81,
    "category": "metalloid",
    "block": "p",
    "group_number": 13,
    "period": 2,
    "state_at_room_temp": "solid",
    "electronegativity": 2.04,
    "ionization_energy": 800.6,
    "electron_affinity": 26.7,
    "atomic_radius": 87.0,
    "density": 2.34,
    "melting_point": 2349.0,
    "boiling_point": 4200.0,
    "discovery_year": 1808,
    "discovered_by": "Joseph Louis Gay-Lussac, Louis Jacques Thenard",
    "electron_configuration": "1s2 2s2 2p1",
    "electron_configuration_semantic": "[He] 2s2 2p1",
    "electrons_per_shell": [
      2,
      3
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 6,
    "symbol": "C",
    "name": "Carbon",
    "atomic_mass": 12.011,
    "category": "nonmetal",
    "block": "p",
    "group_number": 14,
    "period": 2,
    "state_at_room_temp": "solid",
    "electronegativity": 2.55,
    "ionization_energy": 1086.5,
    "electron_affinity": 121.8,
    "atomic_radius": 77.0,
    "density": 2.267,
    "melting_point": 3823.0,
    "boiling_point": 4098.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p2",
    "electron_configuration_semantic": "[He] 2s2 2p2",
    "electrons_per_shell": [
      2,
      4
    ],
    "oxidation_states": "-4, -3, -2, -1, 0, +1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 7,
    "symbol": "N",
    "name": "Nitrogen",
    "atomic_mass": 14.007,
    "category": "nonmetal",
    "block": "p",
    "group_number": 15,
    "period": 2,
    "state_at_room_temp": "gas",
    "electronegativity": 3.04,
    "ionization_energy": 1402.3,
    "electron_affinity": -6.8,
    "atomic_radius": 56.0,
    "density": 0.0012506,
    "melting_point": 63.15,
    "boiling_point": 77.36,
    "discovery_year": 1772,
    "discovered_by": "Daniel Rutherford",
    "electron_configuration": "1s2 2s2 2p3",
    "electron_configuration_semantic": "[He] 2s2 2p3",
    "electrons_per_shell": [
      2,
      5
    ],
    "oxidation_states": "-3, -2, -1, +1, +2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 8,
    "symbol": "O",
    "name": "Oxygen",
    "atomic_mass": 15.999,
    "category": "nonmetal",
    "block": "p",
    "group_number": 16,
    "period": 2,
    "state_at_room_temp": "gas",
    "electronegativity": 3.44,
    "ionization_energy": 1313.9,
    "electron_affinity": 140.98,
    "atomic_radius": 48.0,
    "density": 0.001429,
    "melting_point": 54.36,
    "boiling_point": 90.2,
    "discovery_year": 1771,
    "discovered_by": "Carl Wilhelm Scheele",
    "electron_configuration": "1s2 2s2 2p4",
    "electron_configuration_semantic": "[He] 2s2 2p4",
    "electrons_per_shell": [
      2,
      6
    ],
    "oxidation_states": "-2, -1, +1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 9,
    "symbol": "F",
    "name": "Fluorine",
    "atomic_mass": 18.998,
    "category": "nonmetal",
    "block": "p",
    "group_number": 17,
    "period": 2,
    "state_at_room_temp": "gas",
    "electronegativity": 3.98,
    "ionization_energy": 1681.0,
    "electron_affinity": 328.0,
    "atomic_radius": 42.0,
    "density": 0.001696,
    "melting_point": 53.53,
    "boiling_point": 85.03,
    "discovery_year": 1886,
    "discovered_by": "Andre-Marie Ampere, Henri Moissan",
    "electron_configuration": "1s2 2s2 2p5",
    "electron_configuration_semantic": "[He] 2s2 2p5",
    "electrons_per_shell": [
      2,
      7
    ],
    "oxidation_states": "-1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 10,
    "symbol": "Ne",
    "name": "Neon",
    "atomic_mass": 20.18,
    "category": "noble_gas",
    "block": "p",
    "group_number": 18,
    "period": 2,
    "state_at_room_temp": "gas",
    "electronegativity": null,
    "ionization_energy": 2080.7,
    "electron_affinity": -116.0,
    "atomic_radius": 38.0,
    "density": 0.0008999,
    "melting_point": 24.56,
    "boiling_point": 27.07,
    "discovery_year": 1898,
    "discovered_by": "William Ramsay, Morris Travers",
    "electron_configuration": "1s2 2s2 2p6",
    "electron_configuration_semantic": "[He] 2s2 2p6",
    "electrons_per_shell": [
      2,
      8
    ],
    "oxidation_states": "0",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 11,
    "symbol": "Na",
    "name": "Sodium",
    "atomic_mass": 22.99,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 0.93,
    "ionization_energy": 495.8,
    "electron_affinity": 52.8,
    "atomic_radius": 186.0,
    "density": 0.971,
    "melting_point": 370.87,
    "boiling_point": 1156.0,
    "discovery_year": 1807,
    "discovered_by": "Humphry Davy",
    "electron_configuration": "1s2 2s2 2p6 3s1",
    "electron_configuration_semantic": "[Ne] 3s1",
    "electrons_per_shell": [
      2,
      8,
      1
    ],
    "oxidation_states": "-1, +1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 12,
    "symbol": "Mg",
    "name": "Magnesium",
    "atomic_mass": 24.305,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 1.31,
    "ionization_energy": 737.7,
    "electron_affinity": -40.0,
    "atomic_radius": 160.0,
    "density": 1.738,
    "melting_point": 923.0,
    "boiling_point": 1363.0,
    "discovery_year": 1755,
    "discovered_by": "Joseph Black",
    "electron_configuration": "1s2 2s2 2p6 3s2",
    "electron_configuration_semantic": "[Ne] 3s2",
    "electrons_per_shell": [
      2,
      8,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 13,
    "symbol": "Al",
    "name": "Aluminum",
    "atomic_mass": 26.982,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 13,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 1.61,
    "ionization_energy": 577.5,
    "electron_affinity": 41.8,
    "atomic_radius": 143.0,
    "density": 2.698,
    "melting_point": 933.47,
    "boiling_point": 2792.0,
    "discovery_year": 1825,
    "discovered_by": "Hans Christian Oersted",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p1",
    "electron_configuration_semantic": "[Ne] 3s2 3p1",
    "electrons_per_shell": [
      2,
      8,
      3
    ],
    "oxidation_states": "+1, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 14,
    "symbol": "Si",
    "name": "Silicon",
    "atomic_mass": 28.085,
    "category": "metalloid",
    "block": "p",
    "group_number": 14,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 1.9,
    "ionization_energy": 786.5,
    "electron_affinity": 133.6,
    "atomic_radius": 111.0,
    "density": 2.3296,
    "melting_point": 1687.0,
    "boiling_point": 3538.0,
    "discovery_year": 1824,
    "discovered_by": "Jons Jacob Berzelius",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p2",
    "electron_configuration_semantic": "[Ne] 3s2 3p2",
    "electrons_per_shell": [
      2,
      8,
      4
    ],
    "oxidation_states": "-4, -3, -2, -1, +1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 15,
    "symbol": "P",
    "name": "Phosphorus",
    "atomic_mass": 30.974,
    "category": "nonmetal",
    "block": "p",
    "group_number": 15,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 2.19,
    "ionization_energy": 1011.8,
    "electron_affinity": 72.0,
    "atomic_radius": 98.0,
    "density": 1.82,
    "melting_point": 317.3,
    "boiling_point": 553.65,
    "discovery_year": 1669,
    "discovered_by": "Hennig Brand",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p3",
    "electron_configuration_semantic": "[Ne] 3s2 3p3",
    "electrons_per_shell": [
      2,
      8,
      5
    ],
    "oxidation_states": "-3, -2, -1, +1, +2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 16,
    "symbol": "S",
    "name": "Sulfur",
    "atomic_mass": 32.06,
    "category": "nonmetal",
    "block": "p",
    "group_number": 16,
    "period": 3,
    "state_at_room_temp": "solid",
    "electronegativity": 2.58,
    "ionization_energy": 999.6,
    "electron_affinity": 200.41,
    "atomic_radius": 88.0,
    "density": 2.067,
    "melting_point": 388.36,
    "boiling_point": 717.87,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p4",
    "electron_configuration_semantic": "[Ne] 3s2 3p4",
    "electrons_per_shell": [
      2,
      8,
      6
    ],
    "oxidation_states": "-2, -1, +1, +2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 17,
    "symbol": "Cl",
    "name": "Chlorine",
    "atomic_mass": 35.45,
    "category": "nonmetal",
    "block": "p",
    "group_number": 17,
    "period": 3,
    "state_at_room_temp": "gas",
    "electronegativity": 3.16,
    "ionization_energy": 1251.2,
    "electron_affinity": 349.0,
    "atomic_radius": 79.0,
    "density": 0.003214,
    "melting_point": 171.6,
    "boiling_point": 239.11,
    "discovery_year": 1774,
    "discovered_by": "Carl Wilhelm Scheele",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p5",
    "electron_configuration_semantic": "[Ne] 3s2 3p5",
    "electrons_per_shell": [
      2,
      8,
      7
    ],
    "oxidation_states": "-1, +1, +2, +3, +4, +5, +6, +7",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 18,
    "symbol": "Ar",
    "name": "Argon",
    "atomic_mass": 39.948,
    "category": "noble_gas",
    "block": "p",
    "group_number": 18,
    "period": 3,
    "state_at_room_temp": "gas",
    "electronegativity": null,
    "ionization_energy": 1520.6,
    "electron_affinity": -96.0,
    "atomic_radius": 71.0,
    "density": 0.0017837,
    "melting_point": 83.8,
    "boiling_point": 87.3,
    "discovery_year": 1894,
    "discovered_by": "Lord Rayleigh, William Ramsay",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6",
    "electron_configuration_semantic": "[Ne] 3s2 3p6",
    "electrons_per_shell": [
      2,
      8,
      8
    ],
    "oxidation_states": "0",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 19,
    "symbol": "K",
    "name": "Potassium",
    "atomic_mass": 39.098,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 0.82,
    "ionization_energy": 418.8,
    "electron_affinity": 48.4,
    "atomic_radius": 227.0,
    "density": 0.862,
    "melting_point": 336.53,
    "boiling_point": 1032.0,
    "discovery_year": 1807,
    "discovered_by": "Humphry Davy",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 4s1",
    "electron_configuration_semantic": "[Ar] 4s1",
    "electrons_per_shell": [
      2,
      8,
      8,
      1
    ],
    "oxidation_states": "+1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 20,
    "symbol": "Ca",
    "name": "Calcium",
    "atomic_mass": 40.078,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.0,
    "ionization_energy": 589.8,
    "electron_affinity": 2.37,
    "atomic_radius": 197.0,
    "density": 1.55,
    "melting_point": 1115.0,
    "boiling_point": 1757.0,
    "discovery_year": 1808,
    "discovered_by": "Humphry Davy",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 4s2",
    "electron_configuration_semantic": "[Ar] 4s2",
    "electrons_per_shell": [
      2,
      8,
      8,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 21,
    "symbol": "Sc",
    "name": "Scandium",
    "atomic_mass": 44.956,
    "category": "transition_metal",
    "block": "d",
    "group_number": 3,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.36,
    "ionization_energy": 633.1,
    "electron_affinity": 18.1,
    "atomic_radius": 162.0,
    "density": 2.989,
    "melting_point": 1814.0,
    "boiling_point": 3109.0,
    "discovery_year": 1879,
    "discovered_by": "Lars Fredrik Nilson",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d1 4s2",
    "electron_configuration_semantic": "[Ar] 3d1 4s2",
    "electrons_per_shell": [
      2,
      8,
      9,
      2
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 22,
    "symbol": "Ti",
    "name": "Titanium",
    "atomic_mass": 47.867,
    "category": "transition_metal",
    "block": "d",
    "group_number": 4,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.54,
    "ionization_energy": 658.8,
    "electron_affinity": 7.6,
    "atomic_radius": 147.0,
    "density": 4.54,
    "melting_point": 1941.0,
    "boiling_point": 3560.0,
    "discovery_year": 1791,
    "discovered_by": "William Gregor",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d2 4s2",
    "electron_configuration_semantic": "[Ar] 3d2 4s2",
    "electrons_per_shell": [
      2,
      8,
      10,
      2
    ],
    "oxidation_states": "+2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 23,
    "symbol": "V",
    "name": "Vanadium",
    "atomic_mass": 50.942,
    "category": "transition_metal",
    "block": "d",
    "group_number": 5,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.63,
    "ionization_energy": 650.9,
    "electron_affinity": 50.6,
    "atomic_radius": 134.0,
    "density": 6.11,
    "melting_point": 2183.0,
    "boiling_point": 3680.0,
    "discovery_year": 1801,
    "discovered_by": "Andres Manuel del Rio, Nils Gabriel Sefstrom",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d3 4s2",
    "electron_configuration_semantic": "[Ar] 3d3 4s2",
    "electrons_per_shell": [
      2,
      8,
      11,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 24,
    "symbol": "Cr",
    "name": "Chromium",
    "atomic_mass": 51.996,
    "category": "transition_metal",
    "block": "d",
    "group_number": 6,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.66,
    "ionization_energy": 652.9,
    "electron_affinity": 65.2,
    "atomic_radius": 128.0,
    "density": 7.15,
    "melting_point": 2180.0,
    "boiling_point": 2944.0,
    "discovery_year": 1797,
    "discovered_by": "Louis Nicolas Vauquelin",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d5 4s1",
    "electron_configuration_semantic": "[Ar] 3d5 4s1",
    "electrons_per_shell": [
      2,
      8,
      13,
      1
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 25,
    "symbol": "Mn",
    "name": "Manganese",
    "atomic_mass": 54.938,
    "category": "transition_metal",
    "block": "d",
    "group_number": 7,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.55,
    "ionization_energy": 717.3,
    "electron_affinity": -50.0,
    "atomic_radius": 127.0,
    "density": 7.44,
    "melting_point": 1519.0,
    "boiling_point": 2334.0,
    "discovery_year": 1774,
    "discovered_by": "Johan Gottlieb Gahn",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d5 4s2",
    "electron_configuration_semantic": "[Ar] 3d5 4s2",
    "electrons_per_shell": [
      2,
      8,
      13,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6, +7",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 26,
    "symbol": "Fe",
    "name": "Iron",
    "atomic_mass": 55.845,
    "category": "transition_metal",
    "block": "d",
    "group_number": 8,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.83,
    "ionization_energy": 762.5,
    "electron_affinity": 14.6,
    "atomic_radius": 126.0,
    "density": 7.874,
    "melting_point": 1811.0,
    "boiling_point": 3134.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d6 4s2",
    "electron_configuration_semantic": "[Ar] 3d6 4s2",
    "electrons_per_shell": [
      2,
      8,
      14,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 27,
    "symbol": "Co",
    "name": "Cobalt",
    "atomic_mass": 58.933,
    "category": "transition_metal",
    "block": "d",
    "group_number": 9,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.88,
    "ionization_energy": 760.4,
    "electron_affinity": 63.7,
    "atomic_radius": 125.0,
    "density": 8.9,
    "melting_point": 1768.0,
    "boiling_point": 3200.0,
    "discovery_year": 1735,
    "discovered_by": "Georg Brandt",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d7 4s2",
    "electron_configuration_semantic": "[Ar] 3d7 4s2",
    "electrons_per_shell": [
      2,
      8,
      15,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 28,
    "symbol": "Ni",
    "name": "Nickel",
    "atomic_mass": 58.693,
    "category": "transition_metal",
    "block": "d",
    "group_number": 10,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.91,
    "ionization_energy": 737.1,
    "electron_affinity": 111.7,
    "atomic_radius": 124.0,
    "density": 8.912,
    "melting_point": 1728.0,
    "boiling_point": 3186.0,
    "discovery_year": 1751,
    "discovered_by": "Axel Fredrik Cronstedt",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d8 4s2",
    "electron_configuration_semantic": "[Ar] 3d8 4s2",
    "electrons_per_shell": [
      2,
      8,
      16,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 29,
    "symbol": "Cu",
    "name": "Copper",
    "atomic_mass": 63.546,
    "category": "transition_metal",
    "block": "d",
    "group_number": 11,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.9,
    "ionization_energy": 745.5,
    "electron_affinity": 119.2,
    "atomic_radius": 128.0,
    "density": 8.96,
    "melting_point": 1357.77,
    "boiling_point": 2835.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s1",
    "electron_configuration_semantic": "[Ar] 3d10 4s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      1
    ],
    "oxidation_states": "+1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 30,
    "symbol": "Zn",
    "name": "Zinc",
    "atomic_mass": 65.38,
    "category": "transition_metal",
    "block": "d",
    "group_number": 12,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.65,
    "ionization_energy": 906.4,
    "electron_affinity": -58.0,
    "atomic_radius": 134.0,
    "density": 7.134,
    "melting_point": 692.68,
    "boiling_point": 1180.0,
    "discovery_year": 1746,
    "discovered_by": "Andreas Sigismund Marggraf",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2",
    "electron_configuration_semantic": "[Ar] 3d10 4s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      2
    ],
    "oxidation_states": "+2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 31,
    "symbol": "Ga",
    "name": "Gallium",
    "atomic_mass": 69.723,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 13,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 1.81,
    "ionization_energy": 578.8,
    "electron_affinity": 28.9,
    "atomic_radius": 135.0,
    "density": 5.907,
    "melting_point": 302.91,
    "boiling_point": 2477.0,
    "discovery_year": 1875,
    "discovered_by": "Lecoq de Boisbaudran",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p1",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p1",
    "electrons_per_shell": [
      2,
      8,
      18,
      3
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 32,
    "symbol": "Ge",
    "name": "Germanium",
    "atomic_mass": 72.63,
    "category": "metalloid",
    "block": "p",
    "group_number": 14,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 2.01,
    "ionization_energy": 762.0,
    "electron_affinity": 119.0,
    "atomic_radius": 122.0,
    "density": 5.323,
    "melting_point": 1211.4,
    "boiling_point": 3106.0,
    "discovery_year": 1886,
    "discovered_by": "Clemens Winkler",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p2",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p2",
    "electrons_per_shell": [
      2,
      8,
      18,
      4
    ],
    "oxidation_states": "-4, +1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 33,
    "symbol": "As",
    "name": "Arsenic",
    "atomic_mass": 74.922,
    "category": "metalloid",
    "block": "p",
    "group_number": 15,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 2.18,
    "ionization_energy": 947.0,
    "electron_affinity": 78.2,
    "atomic_radius": 114.0,
    "density": 5.776,
    "melting_point": 1090.0,
    "boiling_point": 887.0,
    "discovery_year": 1250,
    "discovered_by": "Albertus Magnus",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p3",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p3",
    "electrons_per_shell": [
      2,
      8,
      18,
      5
    ],
    "oxidation_states": "-3, +2, +3, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 34,
    "symbol": "Se",
    "name": "Selenium",
    "atomic_mass": 78.971,
    "category": "nonmetal",
    "block": "p",
    "group_number": 16,
    "period": 4,
    "state_at_room_temp": "solid",
    "electronegativity": 2.55,
    "ionization_energy": 941.0,
    "electron_affinity": 195.0,
    "atomic_radius": 103.0,
    "density": 4.809,
    "melting_point": 494.0,
    "boiling_point": 958.0,
    "discovery_year": 1817,
    "discovered_by": "Jons Jacob Berzelius",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p4",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p4",
    "electrons_per_shell": [
      2,
      8,
      18,
      6
    ],
    "oxidation_states": "-2, +2, +4, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 35,
    "symbol": "Br",
    "name": "Bromine",
    "atomic_mass": 79.904,
    "category": "nonmetal",
    "block": "p",
    "group_number": 17,
    "period": 4,
    "state_at_room_temp": "liquid",
    "electronegativity": 2.96,
    "ionization_energy": 1139.9,
    "electron_affinity": 324.6,
    "atomic_radius": 94.0,
    "density": 3.1028,
    "melting_point": 265.8,
    "boiling_point": 332.0,
    "discovery_year": 1826,
    "discovered_by": "Antoine Jerome Balard, Carl Jacob Lowig",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p5",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p5",
    "electrons_per_shell": [
      2,
      8,
      18,
      7
    ],
    "oxidation_states": "-1, +1, +3, +4, +5, +7",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 36,
    "symbol": "Kr",
    "name": "Krypton",
    "atomic_mass": 83.798,
    "category": "noble_gas",
    "block": "p",
    "group_number": 18,
    "period": 4,
    "state_at_room_temp": "gas",
    "electronegativity": 3.0,
    "ionization_energy": 1350.8,
    "electron_affinity": -96.0,
    "atomic_radius": 88.0,
    "density": 0.003733,
    "melting_point": 115.79,
    "boiling_point": 119.93,
    "discovery_year": 1898,
    "discovered_by": "William Ramsay, Morris Travers",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6",
    "electron_configuration_semantic": "[Ar] 3d10 4s2 4p6",
    "electrons_per_shell": [
      2,
      8,
      18,
      8
    ],
    "oxidation_states": "+2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 37,
    "symbol": "Rb",
    "name": "Rubidium",
    "atomic_mass": 85.468,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 0.82,
    "ionization_energy": 403.0,
    "electron_affinity": 46.9,
    "atomic_radius": 248.0,
    "density": 1.532,
    "melting_point": 312.46,
    "boiling_point": 961.0,
    "discovery_year": 1861,
    "discovered_by": "Robert Bunsen, Gustav Kirchhoff",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 5s1",
    "electron_configuration_semantic": "[Kr] 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      8,
      1
    ],
    "oxidation_states": "+1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 38,
    "symbol": "Sr",
    "name": "Strontium",
    "atomic_mass": 87.62,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 0.95,
    "ionization_energy": 549.5,
    "electron_affinity": 5.03,
    "atomic_radius": 215.0,
    "density": 2.64,
    "melting_point": 1050.0,
    "boiling_point": 1655.0,
    "discovery_year": 1790,
    "discovered_by": "Adair Crawford",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 5s2",
    "electron_configuration_semantic": "[Kr] 5s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      8,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 39,
    "symbol": "Y",
    "name": "Yttrium",
    "atomic_mass": 88.906,
    "category": "transition_metal",
    "block": "d",
    "group_number": 3,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.22,
    "ionization_energy": 600.0,
    "electron_affinity": 29.6,
    "atomic_radius": 180.0,
    "density": 4.469,
    "melting_point": 1799.0,
    "boiling_point": 3609.0,
    "discovery_year": 1794,
    "discovered_by": "Johan Gadolin",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d1 5s2",
    "electron_configuration_semantic": "[Kr] 4d1 5s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      9,
      2
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 40,
    "symbol": "Zr",
    "name": "Zirconium",
    "atomic_mass": 91.224,
    "category": "transition_metal",
    "block": "d",
    "group_number": 4,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.33,
    "ionization_energy": 640.1,
    "electron_affinity": 41.1,
    "atomic_radius": 160.0,
    "density": 6.506,
    "melting_point": 2128.0,
    "boiling_point": 4682.0,
    "discovery_year": 1789,
    "discovered_by": "Martin Heinrich Klaproth",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d2 5s2",
    "electron_configuration_semantic": "[Kr] 4d2 5s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      10,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 41,
    "symbol": "Nb",
    "name": "Niobium",
    "atomic_mass": 92.906,
    "category": "transition_metal",
    "block": "d",
    "group_number": 5,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.6,
    "ionization_energy": 652.1,
    "electron_affinity": 86.1,
    "atomic_radius": 146.0,
    "density": 8.57,
    "melting_point": 2750.0,
    "boiling_point": 5017.0,
    "discovery_year": 1801,
    "discovered_by": "Charles Hatchett",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d4 5s1",
    "electron_configuration_semantic": "[Kr] 4d4 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      12,
      1
    ],
    "oxidation_states": "+2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 42,
    "symbol": "Mo",
    "name": "Molybdenum",
    "atomic_mass": 95.95,
    "category": "transition_metal",
    "block": "d",
    "group_number": 6,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.16,
    "ionization_energy": 684.3,
    "electron_affinity": 71.9,
    "atomic_radius": 139.0,
    "density": 10.22,
    "melting_point": 2896.0,
    "boiling_point": 4912.0,
    "discovery_year": 1778,
    "discovered_by": "Carl Wilhelm Scheele",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s1",
    "electron_configuration_semantic": "[Kr] 4d5 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      13,
      1
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 43,
    "symbol": "Tc",
    "name": "Technetium",
    "atomic_mass": 98.0,
    "category": "transition_metal",
    "block": "d",
    "group_number": 7,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.9,
    "ionization_energy": 702.0,
    "electron_affinity": 53.0,
    "atomic_radius": 136.0,
    "density": 11.5,
    "melting_point": 2430.0,
    "boiling_point": 4538.0,
    "discovery_year": 1937,
    "discovered_by": "Carlo Perrier, Emilio Segre",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d5 5s2",
    "electron_configuration_semantic": "[Kr] 4d5 5s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      13,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6, +7",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 44,
    "symbol": "Ru",
    "name": "Ruthenium",
    "atomic_mass": 101.07,
    "category": "transition_metal",
    "block": "d",
    "group_number": 8,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.2,
    "ionization_energy": 710.2,
    "electron_affinity": 101.3,
    "atomic_radius": 134.0,
    "density": 12.37,
    "melting_point": 2607.0,
    "boiling_point": 4423.0,
    "discovery_year": 1844,
    "discovered_by": "Karl Ernst Claus",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d7 5s1",
    "electron_configuration_semantic": "[Kr] 4d7 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      15,
      1
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6, +7, +8",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 45,
    "symbol": "Rh",
    "name": "Rhodium",
    "atomic_mass": 102.91,
    "category": "transition_metal",
    "block": "d",
    "group_number": 9,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.28,
    "ionization_energy": 719.7,
    "electron_affinity": 109.7,
    "atomic_radius": 134.0,
    "density": 12.41,
    "melting_point": 2237.0,
    "boiling_point": 3968.0,
    "discovery_year": 1803,
    "discovered_by": "William Hyde Wollaston",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d8 5s1",
    "electron_configuration_semantic": "[Kr] 4d8 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      16,
      1
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 46,
    "symbol": "Pd",
    "name": "Palladium",
    "atomic_mass": 106.42,
    "category": "transition_metal",
    "block": "d",
    "group_number": 10,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.2,
    "ionization_energy": 804.4,
    "electron_affinity": 53.7,
    "atomic_radius": 137.0,
    "density": 12.02,
    "melting_point": 1828.05,
    "boiling_point": 3236.0,
    "discovery_year": 1803,
    "discovered_by": "William Hyde Wollaston",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10",
    "electron_configuration_semantic": "[Kr] 4d10",
    "electrons_per_shell": [
      2,
      8,
      18,
      18
    ],
    "oxidation_states": "+2, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 47,
    "symbol": "Ag",
    "name": "Silver",
    "atomic_mass": 107.87,
    "category": "transition_metal",
    "block": "d",
    "group_number": 11,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.93,
    "ionization_energy": 731.0,
    "electron_affinity": 125.6,
    "atomic_radius": 144.0,
    "density": 10.501,
    "melting_point": 1234.93,
    "boiling_point": 2435.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s1",
    "electron_configuration_semantic": "[Kr] 4d10 5s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      1
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 48,
    "symbol": "Cd",
    "name": "Cadmium",
    "atomic_mass": 112.41,
    "category": "transition_metal",
    "block": "d",
    "group_number": 12,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.69,
    "ionization_energy": 867.8,
    "electron_affinity": -68.0,
    "atomic_radius": 151.0,
    "density": 8.69,
    "melting_point": 594.22,
    "boiling_point": 1040.0,
    "discovery_year": 1817,
    "discovered_by": "Friedrich Stromeyer, Karl Samuel Leberecht Hermann",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2",
    "electron_configuration_semantic": "[Kr] 4d10 5s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 49,
    "symbol": "In",
    "name": "Indium",
    "atomic_mass": 114.82,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 13,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.78,
    "ionization_energy": 558.3,
    "electron_affinity": 28.9,
    "atomic_radius": 167.0,
    "density": 7.31,
    "melting_point": 429.75,
    "boiling_point": 2345.0,
    "discovery_year": 1863,
    "discovered_by": "Ferdinand Reich, Hieronymous Theodor Richter",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p1",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p1",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      3
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 50,
    "symbol": "Sn",
    "name": "Tin",
    "atomic_mass": 118.71,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 14,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 1.96,
    "ionization_energy": 708.6,
    "electron_affinity": 107.3,
    "atomic_radius": 145.0,
    "density": 7.287,
    "melting_point": 505.08,
    "boiling_point": 2875.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p2",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p2",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      4
    ],
    "oxidation_states": "-4, +2, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 51,
    "symbol": "Sb",
    "name": "Antimony",
    "atomic_mass": 121.76,
    "category": "metalloid",
    "block": "p",
    "group_number": 15,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.05,
    "ionization_energy": 834.0,
    "electron_affinity": 103.2,
    "atomic_radius": 133.0,
    "density": 6.685,
    "melting_point": 903.78,
    "boiling_point": 1860.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p3",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p3",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      5
    ],
    "oxidation_states": "-3, +3, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 52,
    "symbol": "Te",
    "name": "Tellurium",
    "atomic_mass": 127.6,
    "category": "metalloid",
    "block": "p",
    "group_number": 16,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.1,
    "ionization_energy": 869.3,
    "electron_affinity": 190.2,
    "atomic_radius": 123.0,
    "density": 6.232,
    "melting_point": 722.66,
    "boiling_point": 1261.0,
    "discovery_year": 1783,
    "discovered_by": "Franz-Joseph Muller von Reichenstein",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p4",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p4",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      6
    ],
    "oxidation_states": "-2, +2, +4, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 53,
    "symbol": "I",
    "name": "Iodine",
    "atomic_mass": 126.9,
    "category": "nonmetal",
    "block": "p",
    "group_number": 17,
    "period": 5,
    "state_at_room_temp": "solid",
    "electronegativity": 2.66,
    "ionization_energy": 1008.4,
    "electron_affinity": 295.2,
    "atomic_radius": 115.0,
    "density": 4.93,
    "melting_point": 386.85,
    "boiling_point": 457.4,
    "discovery_year": 1811,
    "discovered_by": "Bernard Courtois",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p5",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p5",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      7
    ],
    "oxidation_states": "-1, +1, +3, +5, +7",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 54,
    "symbol": "Xe",
    "name": "Xenon",
    "atomic_mass": 131.29,
    "category": "noble_gas",
    "block": "p",
    "group_number": 18,
    "period": 5,
    "state_at_room_temp": "gas",
    "electronegativity": 2.6,
    "ionization_energy": 1170.4,
    "electron_affinity": -77.0,
    "atomic_radius": 108.0,
    "density": 0.005887,
    "melting_point": 161.36,
    "boiling_point": 165.03,
    "discovery_year": 1898,
    "discovered_by": "William Ramsay, Morris Travers",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6",
    "electron_configuration_semantic": "[Kr] 4d10 5s2 5p6",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      8
    ],
    "oxidation_states": "+2, +4, +6, +8",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 55,
    "symbol": "Cs",
    "name": "Cesium",
    "atomic_mass": 132.91,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 0.79,
    "ionization_energy": 375.7,
    "electron_affinity": 45.5,
    "atomic_radius": 265.0,
    "density": 1.873,
    "melting_point": 301.59,
    "boiling_point": 944.0,
    "discovery_year": 1860,
    "discovered_by": "Robert Bunsen, Gustav Kirchhoff",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s1",
    "electron_configuration_semantic": "[Xe] 6s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      8,
      1
    ],
    "oxidation_states": "+1",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 56,
    "symbol": "Ba",
    "name": "Barium",
    "atomic_mass": 137.33,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 0.89,
    "ionization_energy": 502.9,
    "electron_affinity": 13.95,
    "atomic_radius": 222.0,
    "density": 3.594,
    "melting_point": 1000.0,
    "boiling_point": 2170.0,
    "discovery_year": 1772,
    "discovered_by": "Carl Wilhelm Scheele",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2",
    "electron_configuration_semantic": "[Xe] 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      8,
      2
    ],
    "oxidation_states": "+2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 57,
    "symbol": "La",
    "name": "Lanthanum",
    "atomic_mass": 138.91,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.1,
    "ionization_energy": 538.1,
    "electron_affinity": 53.0,
    "atomic_radius": 187.0,
    "density": 6.145,
    "melting_point": 1193.0,
    "boiling_point": 3737.0,
    "discovery_year": 1839,
    "discovered_by": "Carl Gustaf Mosander",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 5d1 6s2",
    "electron_configuration_semantic": "[Xe] 5d1 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      18,
      9,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 58,
    "symbol": "Ce",
    "name": "Cerium",
    "atomic_mass": 140.12,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.12,
    "ionization_energy": 534.4,
    "electron_affinity": 55.0,
    "atomic_radius": 181.0,
    "density": 6.77,
    "melting_point": 1068.0,
    "boiling_point": 3716.0,
    "discovery_year": 1803,
    "discovered_by": "Jons Jacob Berzelius, Wilhelm Hisinger",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f1 5d1 6s2",
    "electron_configuration_semantic": "[Xe] 4f1 5d1 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      19,
      9,
      2
    ],
    "oxidation_states": "+3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 59,
    "symbol": "Pr",
    "name": "Praseodymium",
    "atomic_mass": 140.91,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.13,
    "ionization_energy": 527.0,
    "electron_affinity": 93.0,
    "atomic_radius": 182.0,
    "density": 6.773,
    "melting_point": 1208.0,
    "boiling_point": 3793.0,
    "discovery_year": 1885,
    "discovered_by": "Carl Auer von Welsbach",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f3 6s2",
    "electron_configuration_semantic": "[Xe] 4f3 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      21,
      8,
      2
    ],
    "oxidation_states": "+2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 60,
    "symbol": "Nd",
    "name": "Neodymium",
    "atomic_mass": 144.24,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.14,
    "ionization_energy": 533.1,
    "electron_affinity": 184.9,
    "atomic_radius": 181.0,
    "density": 7.007,
    "melting_point": 1297.0,
    "boiling_point": 3347.0,
    "discovery_year": 1885,
    "discovered_by": "Carl Auer von Welsbach",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f4 6s2",
    "electron_configuration_semantic": "[Xe] 4f4 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      22,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 61,
    "symbol": "Pm",
    "name": "Promethium",
    "atomic_mass": 145.0,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.13,
    "ionization_energy": 540.0,
    "electron_affinity": 12.45,
    "atomic_radius": 183.0,
    "density": 7.26,
    "melting_point": 1315.0,
    "boiling_point": 3273.0,
    "discovery_year": 1945,
    "discovered_by": "Charles D. Coryell, Jacob A. Marinsky, Lawrence E. Glendenin",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f5 6s2",
    "electron_configuration_semantic": "[Xe] 4f5 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      23,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 62,
    "symbol": "Sm",
    "name": "Samarium",
    "atomic_mass": 150.36,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.17,
    "ionization_energy": 544.5,
    "electron_affinity": 15.6,
    "atomic_radius": 180.0,
    "density": 7.52,
    "melting_point": 1345.0,
    "boiling_point": 2067.0,
    "discovery_year": 1879,
    "discovered_by": "Lecoq de Boisbaudran",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f6 6s2",
    "electron_configuration_semantic": "[Xe] 4f6 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      24,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 63,
    "symbol": "Eu",
    "name": "Europium",
    "atomic_mass": 151.96,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.2,
    "ionization_energy": 547.1,
    "electron_affinity": 11.2,
    "atomic_radius": 180.0,
    "density": 5.243,
    "melting_point": 1099.0,
    "boiling_point": 1802.0,
    "discovery_year": 1901,
    "discovered_by": "Eugene-Anatole Demarcay",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f7 6s2",
    "electron_configuration_semantic": "[Xe] 4f7 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      25,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 64,
    "symbol": "Gd",
    "name": "Gadolinium",
    "atomic_mass": 157.25,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.2,
    "ionization_energy": 593.4,
    "electron_affinity": 13.22,
    "atomic_radius": 180.0,
    "density": 7.895,
    "melting_point": 1585.0,
    "boiling_point": 3546.0,
    "discovery_year": 1880,
    "discovered_by": "Jean Charles Galissard de Marignac",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f7 5d1 6s2",
    "electron_configuration_semantic": "[Xe] 4f7 5d1 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      25,
      9,
      2
    ],
    "oxidation_states": "+1, +2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 65,
    "symbol": "Tb",
    "name": "Terbium",
    "atomic_mass": 158.93,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.2,
    "ionization_energy": 565.8,
    "electron_affinity": 112.4,
    "atomic_radius": 177.0,
    "density": 8.229,
    "melting_point": 1629.0,
    "boiling_point": 3503.0,
    "discovery_year": 1843,
    "discovered_by": "Carl Gustaf Mosander",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f9 6s2",
    "electron_configuration_semantic": "[Xe] 4f9 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      27,
      8,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 66,
    "symbol": "Dy",
    "name": "Dysprosium",
    "atomic_mass": 162.5,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.22,
    "ionization_energy": 573.0,
    "electron_affinity": 33.96,
    "atomic_radius": 178.0,
    "density": 8.55,
    "melting_point": 1680.0,
    "boiling_point": 2840.0,
    "discovery_year": 1886,
    "discovered_by": "Lecoq de Boisbaudran",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f10 6s2",
    "electron_configuration_semantic": "[Xe] 4f10 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      28,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 67,
    "symbol": "Ho",
    "name": "Holmium",
    "atomic_mass": 164.93,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.23,
    "ionization_energy": 581.0,
    "electron_affinity": 32.61,
    "atomic_radius": 176.0,
    "density": 8.795,
    "melting_point": 1734.0,
    "boiling_point": 2993.0,
    "discovery_year": 1878,
    "discovered_by": "Per Teodor Cleve",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f11 6s2",
    "electron_configuration_semantic": "[Xe] 4f11 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      29,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 68,
    "symbol": "Er",
    "name": "Erbium",
    "atomic_mass": 167.26,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.24,
    "ionization_energy": 589.3,
    "electron_affinity": 30.1,
    "atomic_radius": 176.0,
    "density": 9.066,
    "melting_point": 1802.0,
    "boiling_point": 3141.0,
    "discovery_year": 1843,
    "discovered_by": "Carl Gustaf Mosander",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f12 6s2",
    "electron_configuration_semantic": "[Xe] 4f12 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      30,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 69,
    "symbol": "Tm",
    "name": "Thulium",
    "atomic_mass": 168.93,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.25,
    "ionization_energy": 596.7,
    "electron_affinity": 99.0,
    "atomic_radius": 176.0,
    "density": 9.321,
    "melting_point": 1818.0,
    "boiling_point": 2223.0,
    "discovery_year": 1879,
    "discovered_by": "Per Teodor Cleve",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f13 6s2",
    "electron_configuration_semantic": "[Xe] 4f13 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      31,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 70,
    "symbol": "Yb",
    "name": "Ytterbium",
    "atomic_mass": 173.05,
    "category": "lanthanide",
    "block": "f",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.1,
    "ionization_energy": 603.4,
    "electron_affinity": -1.93,
    "atomic_radius": 176.0,
    "density": 6.965,
    "melting_point": 1097.0,
    "boiling_point": 1469.0,
    "discovery_year": 1878,
    "discovered_by": "Jean Charles Galissard de Marignac",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 71,
    "symbol": "Lu",
    "name": "Lutetium",
    "atomic_mass": 174.97,
    "category": "lanthanide",
    "block": "d",
    "group_number": null,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.27,
    "ionization_energy": 523.5,
    "electron_affinity": 33.4,
    "atomic_radius": 174.0,
    "density": 9.84,
    "melting_point": 1925.0,
    "boiling_point": 3675.0,
    "discovery_year": 1907,
    "discovered_by": "Georges Urbain, Carl Auer von Welsbach",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d1 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d1 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      9,
      2
    ],
    "oxidation_states": "+3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 72,
    "symbol": "Hf",
    "name": "Hafnium",
    "atomic_mass": 178.49,
    "category": "transition_metal",
    "block": "d",
    "group_number": 4,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 658.5,
    "electron_affinity": 17.18,
    "atomic_radius": 159.0,
    "density": 13.31,
    "melting_point": 2506.0,
    "boiling_point": 4876.0,
    "discovery_year": 1923,
    "discovered_by": "Dirk Coster, George de Hevesy",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d2 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d2 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      10,
      2
    ],
    "oxidation_states": "+2, +3, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 73,
    "symbol": "Ta",
    "name": "Tantalum",
    "atomic_mass": 180.95,
    "category": "transition_metal",
    "block": "d",
    "group_number": 5,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.5,
    "ionization_energy": 761.0,
    "electron_affinity": 31.0,
    "atomic_radius": 146.0,
    "density": 16.654,
    "melting_point": 3290.0,
    "boiling_point": 5731.0,
    "discovery_year": 1802,
    "discovered_by": "Anders Gustaf Ekeberg",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d3 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d3 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      11,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 74,
    "symbol": "W",
    "name": "Tungsten",
    "atomic_mass": 183.84,
    "category": "transition_metal",
    "block": "d",
    "group_number": 6,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.36,
    "ionization_energy": 770.0,
    "electron_affinity": 78.6,
    "atomic_radius": 139.0,
    "density": 19.25,
    "melting_point": 3695.0,
    "boiling_point": 5828.0,
    "discovery_year": 1783,
    "discovered_by": "Juan Jose Elhuyar, Fausto Elhuyar",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d4 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d4 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      12,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 75,
    "symbol": "Re",
    "name": "Rhenium",
    "atomic_mass": 186.21,
    "category": "transition_metal",
    "block": "d",
    "group_number": 7,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.9,
    "ionization_energy": 760.0,
    "electron_affinity": 5.8,
    "atomic_radius": 137.0,
    "density": 21.02,
    "melting_point": 3459.0,
    "boiling_point": 5869.0,
    "discovery_year": 1925,
    "discovered_by": "Masataka Ogawa, Walter Noddack, Ida Tacke, Otto Berg",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d5 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d5 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      13,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6, +7",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 76,
    "symbol": "Os",
    "name": "Osmium",
    "atomic_mass": 190.23,
    "category": "transition_metal",
    "block": "d",
    "group_number": 8,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.2,
    "ionization_energy": 840.0,
    "electron_affinity": 103.99,
    "atomic_radius": 135.0,
    "density": 22.587,
    "melting_point": 3306.0,
    "boiling_point": 5285.0,
    "discovery_year": 1803,
    "discovered_by": "Smithson Tennant",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d6 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d6 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      14,
      2
    ],
    "oxidation_states": "+2, +3, +4, +6, +8",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 77,
    "symbol": "Ir",
    "name": "Iridium",
    "atomic_mass": 192.22,
    "category": "transition_metal",
    "block": "d",
    "group_number": 9,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.2,
    "ionization_energy": 880.0,
    "electron_affinity": 150.94,
    "atomic_radius": 136.0,
    "density": 22.56,
    "melting_point": 2719.0,
    "boiling_point": 4701.0,
    "discovery_year": 1803,
    "discovered_by": "Smithson Tennant",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d7 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d7 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      15,
      2
    ],
    "oxidation_states": "+1, +2, +3, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 78,
    "symbol": "Pt",
    "name": "Platinum",
    "atomic_mass": 195.08,
    "category": "transition_metal",
    "block": "d",
    "group_number": 10,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.28,
    "ionization_energy": 870.0,
    "electron_affinity": 205.3,
    "atomic_radius": 139.0,
    "density": 21.46,
    "melting_point": 2041.4,
    "boiling_point": 4098.0,
    "discovery_year": 1735,
    "discovered_by": "Antonio de Ulloa, Charles Wood",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d9 6s1",
    "electron_configuration_semantic": "[Xe] 4f14 5d9 6s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      17,
      1
    ],
    "oxidation_states": "+2, +4, +5, +6",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 79,
    "symbol": "Au",
    "name": "Gold",
    "atomic_mass": 196.97,
    "category": "transition_metal",
    "block": "d",
    "group_number": 11,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.54,
    "ionization_energy": 890.1,
    "electron_affinity": 222.8,
    "atomic_radius": 144.0,
    "density": 19.282,
    "melting_point": 1337.33,
    "boiling_point": 3129.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s1",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      1
    ],
    "oxidation_states": "+1, +2, +3, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 80,
    "symbol": "Hg",
    "name": "Mercury",
    "atomic_mass": 200.59,
    "category": "transition_metal",
    "block": "d",
    "group_number": 12,
    "period": 6,
    "state_at_room_temp": "liquid",
    "electronegativity": 2.0,
    "ionization_energy": 1007.1,
    "electron_affinity": -48.0,
    "atomic_radius": 151.0,
    "density": 13.5336,
    "melting_point": 234.32,
    "boiling_point": 629.88,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      2
    ],
    "oxidation_states": "+1, +2",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 81,
    "symbol": "Tl",
    "name": "Thallium",
    "atomic_mass": 204.38,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 13,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 1.62,
    "ionization_energy": 589.4,
    "electron_affinity": 19.2,
    "atomic_radius": 170.0,
    "density": 11.85,
    "melting_point": 577.0,
    "boiling_point": 1746.0,
    "discovery_year": 1861,
    "discovered_by": "William Crookes",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p1",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      3
    ],
    "oxidation_states": "+1, +3",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 82,
    "symbol": "Pb",
    "name": "Lead",
    "atomic_mass": 207.2,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 14,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.33,
    "ionization_energy": 715.6,
    "electron_affinity": 35.1,
    "atomic_radius": 175.0,
    "density": 11.342,
    "melting_point": 600.61,
    "boiling_point": 2022.0,
    "discovery_year": null,
    "discovered_by": "Known since antiquity",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p2",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      4
    ],
    "oxidation_states": "-4, +2, +4",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 83,
    "symbol": "Bi",
    "name": "Bismuth",
    "atomic_mass": 208.98,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 15,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.02,
    "ionization_energy": 703.0,
    "electron_affinity": 91.2,
    "atomic_radius": 156.0,
    "density": 9.807,
    "melting_point": 544.7,
    "boiling_point": 1837.0,
    "discovery_year": 1753,
    "discovered_by": "Claude Francois Geoffroy",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p3",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p3",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      5
    ],
    "oxidation_states": "-3, +3, +5",
    "is_radioactive": false,
    "is_synthetic": false
  },
  {
    "atomic_number": 84,
    "symbol": "Po",
    "name": "Polonium",
    "atomic_mass": 208.98243,
    "category": "post_transition_metal",
    "block": "p",
    "group_number": 16,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.0,
    "ionization_energy": 812.1,
    "electron_affinity": 183.3,
    "atomic_radius": 168.0,
    "density": 9.32,
    "melting_point": 527.0,
    "boiling_point": 1235.0,
    "discovery_year": 1898,
    "discovered_by": "Marie Curie, Pierre Curie",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p4",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p4",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      6
    ],
    "oxidation_states": "-2, +2, +4, +6",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 85,
    "symbol": "At",
    "name": "Astatine",
    "atomic_mass": 209.98715,
    "category": "nonmetal",
    "block": "p",
    "group_number": 17,
    "period": 6,
    "state_at_room_temp": "solid",
    "electronegativity": 2.2,
    "ionization_energy": 899.0,
    "electron_affinity": 270.1,
    "atomic_radius": 150.0,
    "density": 7.0,
    "melting_point": 575.0,
    "boiling_point": 610.0,
    "discovery_year": 1940,
    "discovered_by": "Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segre",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p5",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p5",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      7
    ],
    "oxidation_states": "-1, +1, +3, +5, +7",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 86,
    "symbol": "Rn",
    "name": "Radon",
    "atomic_mass": 222.01758,
    "category": "noble_gas",
    "block": "p",
    "group_number": 18,
    "period": 6,
    "state_at_room_temp": "gas",
    "electronegativity": 2.2,
    "ionization_energy": 1037.0,
    "electron_affinity": -68.0,
    "atomic_radius": 150.0,
    "density": 0.00973,
    "melting_point": 202.0,
    "boiling_point": 211.3,
    "discovery_year": 1900,
    "discovered_by": "Friedrich Ernst Dorn",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6",
    "electron_configuration_semantic": "[Xe] 4f14 5d10 6s2 6p6",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      8
    ],
    "oxidation_states": "+2, +6",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 87,
    "symbol": "Fr",
    "name": "Francium",
    "atomic_mass": 223.01973,
    "category": "alkali_metal",
    "block": "s",
    "group_number": 1,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 0.7,
    "ionization_energy": 380.0,
    "electron_affinity": 46.89,
    "atomic_radius": 260.0,
    "density": 1.87,
    "melting_point": 300.0,
    "boiling_point": 950.0,
    "discovery_year": 1939,
    "discovered_by": "Marguerite Perey",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 7s1",
    "electron_configuration_semantic": "[Rn] 7s1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      8,
      1
    ],
    "oxidation_states": "+1",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 88,
    "symbol": "Ra",
    "name": "Radium",
    "atomic_mass": 226.02541,
    "category": "alkaline_earth_metal",
    "block": "s",
    "group_number": 2,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 0.9,
    "ionization_energy": 509.3,
    "electron_affinity": 9.65,
    "atomic_radius": 221.0,
    "density": 5.5,
    "melting_point": 973.0,
    "boiling_point": 2010.0,
    "discovery_year": 1898,
    "discovered_by": "Marie Curie, Pierre Curie",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 7s2",
    "electron_configuration_semantic": "[Rn] 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      8,
      2
    ],
    "oxidation_states": "+2",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 89,
    "symbol": "Ac",
    "name": "Actinium",
    "atomic_mass": 227.02775,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.1,
    "ionization_energy": 499.0,
    "electron_affinity": 33.77,
    "atomic_radius": 195.0,
    "density": 10.07,
    "melting_point": 1323.0,
    "boiling_point": 3471.0,
    "discovery_year": 1899,
    "discovered_by": "Friedrich Oskar Giesel, Andre-Louis Debierne",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 6d1 7s2",
    "electron_configuration_semantic": "[Rn] 6d1 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      9,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 90,
    "symbol": "Th",
    "name": "Thorium",
    "atomic_mass": 232.038,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 587.0,
    "electron_affinity": 112.72,
    "atomic_radius": 180.0,
    "density": 11.72,
    "melting_point": 2115.0,
    "boiling_point": 5061.0,
    "discovery_year": 1829,
    "discovered_by": "Jons Jacob Berzelius",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 6d2 7s2",
    "electron_configuration_semantic": "[Rn] 6d2 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      18,
      10,
      2
    ],
    "oxidation_states": "+2, +3, +4",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 91,
    "symbol": "Pa",
    "name": "Protactinium",
    "atomic_mass": 231.03588,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.5,
    "ionization_energy": 568.0,
    "electron_affinity": 53.03,
    "atomic_radius": 163.0,
    "density": 15.37,
    "melting_point": 1841.0,
    "boiling_point": 4300.0,
    "discovery_year": 1913,
    "discovered_by": "Kasimir Fajans, Oswald Helmuth Gohring",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f2 6d1 7s2",
    "electron_configuration_semantic": "[Rn] 5f2 6d1 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      20,
      9,
      2
    ],
    "oxidation_states": "+3, +4, +5",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 92,
    "symbol": "U",
    "name": "Uranium",
    "atomic_mass": 238.0289,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.38,
    "ionization_energy": 597.6,
    "electron_affinity": 50.94,
    "atomic_radius": 156.0,
    "density": 19.1,
    "melting_point": 1405.3,
    "boiling_point": 4404.0,
    "discovery_year": 1789,
    "discovered_by": "Martin Heinrich Klaproth",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f3 6d1 7s2",
    "electron_configuration_semantic": "[Rn] 5f3 6d1 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      21,
      9,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5, +6",
    "is_radioactive": true,
    "is_synthetic": false
  },
  {
    "atomic_number": 93,
    "symbol": "Np",
    "name": "Neptunium",
    "atomic_mass": 237.04817,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.36,
    "ionization_energy": 604.5,
    "electron_affinity": 45.85,
    "atomic_radius": 155.0,
    "density": 20.45,
    "melting_point": 917.0,
    "boiling_point": 4273.0,
    "discovery_year": 1940,
    "discovered_by": "Edwin McMillan, Philip Abelson",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f4 6d1 7s2",
    "electron_configuration_semantic": "[Rn] 5f4 6d1 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      22,
      9,
      2
    ],
    "oxidation_states": "+3, +4, +5, +6, +7",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 94,
    "symbol": "Pu",
    "name": "Plutonium",
    "atomic_mass": 244.0642,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.28,
    "ionization_energy": 584.7,
    "electron_affinity": -48.33,
    "atomic_radius": 159.0,
    "density": 19.84,
    "melting_point": 912.5,
    "boiling_point": 3501.0,
    "discovery_year": 1940,
    "discovered_by": "Glenn T. Seaborg, Arthur Wahl, Joseph W. Kennedy, Edwin McMillan",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f6 7s2",
    "electron_configuration_semantic": "[Rn] 5f6 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      24,
      8,
      2
    ],
    "oxidation_states": "+3, +4, +5, +6, +7",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 95,
    "symbol": "Am",
    "name": "Americium",
    "atomic_mass": 243.06138,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 578.0,
    "electron_affinity": 9.93,
    "atomic_radius": 173.0,
    "density": 13.69,
    "melting_point": 1449.0,
    "boiling_point": 2880.0,
    "discovery_year": 1944,
    "discovered_by": "Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f7 7s2",
    "electron_configuration_semantic": "[Rn] 5f7 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      25,
      8,
      2
    ],
    "oxidation_states": "+2, +3, +4, +5, +6, +7",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 96,
    "symbol": "Cm",
    "name": "Curium",
    "atomic_mass": 247.07035,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 581.0,
    "electron_affinity": 27.17,
    "atomic_radius": 174.0,
    "density": 13.51,
    "melting_point": 1613.0,
    "boiling_point": 3383.0,
    "discovery_year": 1944,
    "discovered_by": "Glenn T. Seaborg, Ralph A. James, Albert Ghiorso",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f7 6d1 7s2",
    "electron_configuration_semantic": "[Rn] 5f7 6d1 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      25,
      9,
      2
    ],
    "oxidation_states": "+3, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 97,
    "symbol": "Bk",
    "name": "Berkelium",
    "atomic_mass": 247.07031,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 601.0,
    "electron_affinity": -165.24,
    "atomic_radius": 170.0,
    "density": 14.79,
    "melting_point": 1259.0,
    "boiling_point": 2900.0,
    "discovery_year": 1949,
    "discovered_by": "Stanley G. Thompson, Albert Ghiorso, Glenn T. Seaborg",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f9 7s2",
    "electron_configuration_semantic": "[Rn] 5f9 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      27,
      8,
      2
    ],
    "oxidation_states": "+3, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 98,
    "symbol": "Cf",
    "name": "Californium",
    "atomic_mass": 251.07959,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 608.0,
    "electron_affinity": -97.31,
    "atomic_radius": 169.0,
    "density": 15.1,
    "melting_point": 1173.0,
    "boiling_point": 1743.0,
    "discovery_year": 1950,
    "discovered_by": "Stanley G. Thompson, Kenneth Street Jr., Albert Ghiorso, Glenn T. Seaborg",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f10 7s2",
    "electron_configuration_semantic": "[Rn] 5f10 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      28,
      8,
      2
    ],
    "oxidation_states": "+2, +3, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 99,
    "symbol": "Es",
    "name": "Einsteinium",
    "atomic_mass": 252.083,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 619.0,
    "electron_affinity": -28.6,
    "atomic_radius": 203.0,
    "density": 8.84,
    "melting_point": 1133.0,
    "boiling_point": 1269.0,
    "discovery_year": 1952,
    "discovered_by": "Albert Ghiorso and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f11 7s2",
    "electron_configuration_semantic": "[Rn] 5f11 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      29,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 100,
    "symbol": "Fm",
    "name": "Fermium",
    "atomic_mass": 257.09511,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 627.0,
    "electron_affinity": 33.96,
    "atomic_radius": null,
    "density": 9.7,
    "melting_point": 1800.0,
    "boiling_point": null,
    "discovery_year": 1952,
    "discovered_by": "Albert Ghiorso and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f12 7s2",
    "electron_configuration_semantic": "[Rn] 5f12 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      30,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 101,
    "symbol": "Md",
    "name": "Mendelevium",
    "atomic_mass": 258.09843,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 635.0,
    "electron_affinity": -93.91,
    "atomic_radius": null,
    "density": 10.3,
    "melting_point": 1100.0,
    "boiling_point": null,
    "discovery_year": 1955,
    "discovered_by": "Albert Ghiorso, Bernard G. Harvey, Gregory R. Choppin, Stanley G. Thompson, Glenn T. Seaborg",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f13 7s2",
    "electron_configuration_semantic": "[Rn] 5f13 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      31,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 102,
    "symbol": "No",
    "name": "Nobelium",
    "atomic_mass": 259.101,
    "category": "actinide",
    "block": "f",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 642.0,
    "electron_affinity": -223.22,
    "atomic_radius": null,
    "density": 9.9,
    "melting_point": 1100.0,
    "boiling_point": null,
    "discovery_year": 1966,
    "discovered_by": "Joint Institute for Nuclear Research (Dubna)",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      8,
      2
    ],
    "oxidation_states": "+2, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 103,
    "symbol": "Lr",
    "name": "Lawrencium",
    "atomic_mass": 266.12,
    "category": "actinide",
    "block": "d",
    "group_number": null,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": 1.3,
    "ionization_energy": 470.0,
    "electron_affinity": -30.04,
    "atomic_radius": null,
    "density": 15.6,
    "melting_point": 1900.0,
    "boiling_point": null,
    "discovery_year": 1961,
    "discovered_by": "Albert Ghiorso, Torbjorn Sikkeland, Almon Larsh, Robert M. Latimer",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 7s2 7p1",
    "electron_configuration_semantic": "[Rn] 5f14 7s2 7p1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      8,
      3
    ],
    "oxidation_states": "+3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 104,
    "symbol": "Rf",
    "name": "Rutherfordium",
    "atomic_mass": 267.122,
    "category": "transition_metal",
    "block": "d",
    "group_number": 4,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": 580.0,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 23.2,
    "melting_point": 2400.0,
    "boiling_point": 5800.0,
    "discovery_year": 1964,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Berkeley National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d2 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d2 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      10,
      2
    ],
    "oxidation_states": "+4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 105,
    "symbol": "Db",
    "name": "Dubnium",
    "atomic_mass": 268.126,
    "category": "transition_metal",
    "block": "d",
    "group_number": 5,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 29.3,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1968,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Berkeley National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d3 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d3 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      11,
      2
    ],
    "oxidation_states": "+5",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 106,
    "symbol": "Sg",
    "name": "Seaborgium",
    "atomic_mass": 269.128,
    "category": "transition_metal",
    "block": "d",
    "group_number": 6,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 35.0,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1974,
    "discovered_by": "Albert Ghiorso and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d4 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d4 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      12,
      2
    ],
    "oxidation_states": "+6",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 107,
    "symbol": "Bh",
    "name": "Bohrium",
    "atomic_mass": 270.133,
    "category": "transition_metal",
    "block": "d",
    "group_number": 7,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 37.1,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1981,
    "discovered_by": "Peter Armbruster, Gottfried Munzenberg and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d5 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d5 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      13,
      2
    ],
    "oxidation_states": "+7",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 108,
    "symbol": "Hs",
    "name": "Hassium",
    "atomic_mass": 269.1336,
    "category": "transition_metal",
    "block": "d",
    "group_number": 8,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 40.7,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1984,
    "discovered_by": "Peter Armbruster, Gottfried Munzenberg and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d6 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d6 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      14,
      2
    ],
    "oxidation_states": "+8",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 109,
    "symbol": "Mt",
    "name": "Meitnerium",
    "atomic_mass": 277.154,
    "category": "unknown",
    "block": "d",
    "group_number": 9,
    "period": 7,
    "state_at_room_temp": "solid",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 37.4,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1982,
    "discovered_by": "Peter Armbruster, Gottfried Munzenberg and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d7 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d7 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      15,
      2
    ],
    "oxidation_states": "+1, +3, +6, +9",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 110,
    "symbol": "Ds",
    "name": "Darmstadtium",
    "atomic_mass": 282.166,
    "category": "unknown",
    "block": "d",
    "group_number": 10,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 34.8,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1994,
    "discovered_by": "Peter Armbruster, Gottfried Munzenberg and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d8 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d8 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      16,
      2
    ],
    "oxidation_states": "+2, +4, +6, +8",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 111,
    "symbol": "Rg",
    "name": "Roentgenium",
    "atomic_mass": 282.169,
    "category": "unknown",
    "block": "d",
    "group_number": 11,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 28.7,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1994,
    "discovered_by": "Peter Armbruster, Gottfried Munzenberg and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d9 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d9 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      17,
      2
    ],
    "oxidation_states": "+1, +3, +5",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 112,
    "symbol": "Cn",
    "name": "Copernicium",
    "atomic_mass": 286.179,
    "category": "unknown",
    "block": "d",
    "group_number": 12,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 23.7,
    "melting_point": null,
    "boiling_point": null,
    "discovery_year": 1996,
    "discovered_by": "Sigurd Hofmann and others",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      2
    ],
    "oxidation_states": "+2, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 113,
    "symbol": "Nh",
    "name": "Nihonium",
    "atomic_mass": 286.182,
    "category": "unknown",
    "block": "p",
    "group_number": 13,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 16.0,
    "melting_point": 700.0,
    "boiling_point": 1400.0,
    "discovery_year": 2004,
    "discovered_by": "Kosuke Morita and others (RIKEN)",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p1",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p1",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      3
    ],
    "oxidation_states": "+1, +3, +5",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 114,
    "symbol": "Fl",
    "name": "Flerovium",
    "atomic_mass": 290.192,
    "category": "unknown",
    "block": "p",
    "group_number": 14,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 14.0,
    "melting_point": 340.0,
    "boiling_point": 420.0,
    "discovery_year": 1999,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Livermore National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p2",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p2",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      4
    ],
    "oxidation_states": "+2, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 115,
    "symbol": "Mc",
    "name": "Moscovium",
    "atomic_mass": 290.196,
    "category": "unknown",
    "block": "p",
    "group_number": 15,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 13.5,
    "melting_point": 670.0,
    "boiling_point": 1400.0,
    "discovery_year": 2003,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Livermore National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p3",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p3",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      5
    ],
    "oxidation_states": "+1, +3",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 116,
    "symbol": "Lv",
    "name": "Livermorium",
    "atomic_mass": 293.205,
    "category": "unknown",
    "block": "p",
    "group_number": 16,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 12.9,
    "melting_point": 709.0,
    "boiling_point": 1085.0,
    "discovery_year": 2000,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Livermore National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p4",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p4",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      6
    ],
    "oxidation_states": "+2, +4",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 117,
    "symbol": "Ts",
    "name": "Tennessine",
    "atomic_mass": 294.211,
    "category": "unknown",
    "block": "p",
    "group_number": 17,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 7.2,
    "melting_point": 723.0,
    "boiling_point": 883.0,
    "discovery_year": 2010,
    "discovered_by": "Joint Institute for Nuclear Research / Oak Ridge National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p5",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p5",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      7
    ],
    "oxidation_states": "+1, +3, +5",
    "is_radioactive": true,
    "is_synthetic": true
  },
  {
    "atomic_number": 118,
    "symbol": "Og",
    "name": "Oganesson",
    "atomic_mass": 295.216,
    "category": "unknown",
    "block": "p",
    "group_number": 18,
    "period": 7,
    "state_at_room_temp": "unknown",
    "electronegativity": null,
    "ionization_energy": null,
    "electron_affinity": null,
    "atomic_radius": null,
    "density": 5.0,
    "melting_point": null,
    "boiling_point": 350.0,
    "discovery_year": 2002,
    "discovered_by": "Joint Institute for Nuclear Research / Lawrence Livermore National Laboratory",
    "electron_configuration": "1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f14 6d10 7s2 7p6",
    "electron_configuration_semantic": "[Rn] 5f14 6d10 7s2 7p6",
    "electrons_per_shell": [
      2,
      8,
      18,
      32,
      32,
      18,
      8
    ],
    "oxidation_states": "-1, 0, +1, +2, +4, +6",
    "is_radioactive": true,
    "is_synthetic": true
  }
]