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A6: Atomic Ionization Energies

  • Page ID
    11260
  • Ionization energy is the quantity of energy that an isolated, gaseous atom in the ground electronic state must absorb to discharge an electron, resulting in a gaseous cation.

    \[ H(g) \rightarrow H^+(g) + e^- \]

    These tables list values of molar ionization energies, measured in kJ mol-1.

    number symbol name 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
    1 H hydrogen 2372.3 5250.5
    3 Li lithium 520.2 7298.1 11815.0
    4 Be beryllium 899.5 1757.1 14848.7 21006.6
    5 B boron 800.6 2427.1 3659.7 25025.8 32826.7
    6 C carbon 1086.5 2352.6 4620.5 6222.7 37831 47277.0
    7 N nitrogen 1402.3 2856 4578.1 7475.0 9444.9 53266.6 64360
    8 O oxygen 1313.9 3388.3 5300.5 7469.2 10989.5 13326.5 71330 84078.0
    9 F fluorine 1681.0 3374.2 6050.4 8407.7 11022.7 15164.1 17868 92038.1 106434.3
    10 Ne neon 2080.7 3952.3 6122 9371 12177 15238 19999.0 23069.5 115379.5 131432
    11 Na sodium 495.8 4562 6910.3 9543 13354 16613 20117 25496 28932 141362
    12 Mg magnesium 737.7 1450.7 7732.7 10542.5 13630 18020 21711 25661 31653 35458
    13 Al aluminium 577.5 1816.7 2744.8 11577 14842 18379 23326 27465 31853 38473
    14 Si silicon 786.5 1577.1 3231.6 4355.5 16091 19805 23780 29287 33878 38726
    15 P phosphorus 1011.8 1907 2914.1 4963.6 6273.9 21267 25431 29872 35905 40950
    16 S sulfur 999.6 2252 3357 4556 7004.3 8495.8 27107 31719 36621 43177
    17 Cl chlorine 1251.2 2298 3822 5158.6 6542 9362 11018 33604 38600 43961
    18 Ar argon 1520.6 2665.8 3931 5771 7238 8781 11995 13842 40760 46186
    19 K potassium 418.8 3052 4420 5877 7975 9590 11343 14944 16963.7 48610
    20 Ca calcium 589.8 1145.4 4912.4 6491 8153 10496 12270 14206 18191 20385
    21 Sc scandium 633.1 1235.0 2388.6 7090.6 8843 10679 13310 15250 17370 21726
    22 Ti titanium 658.8 1309.8 2652.5 4174.6 9581 11533 13590 16440 18530 20833
    23 V vanadium 650.9 1414 2830 4507 6298.7 12363 14530 16730 19860 22240
    24 Cr chromium 652.9 1590.6 2987 4743 6702 8744.9 15455 17820 20190 23580
    25 Mn manganese 717.3 1509.0 3248 4940 6990 9220 11500 18770 21400 23960
    26 Fe iron 762.5 1561.9 2957 5290 7240 9560 12060 14580 22540 25290
    27 Co cobalt 760.4 1648 3232 4950 7670 9840 12440 15230 17959 26570
    28 Ni nickel 737.1 1753.0 3395 5300 7339 10400 12800 15600 18600 21670
    29 Cu copper 745.5 1957.9 3555 5536 7700 9900 13400 16000 19200 22400
    30 Zn zinc 906.4 1733.3 3833 5731 7970 10400 12900 16800 19600 23000
    31 Ga gallium 578.8 1979.3 2963 6180
    32 Ge germanium 762 1537.5 3302.1 4411 9020
    33 As arsenic 947.0 1798 2735 4837 6043 12310
    34 Se selenium 941.0 2045 2973.7 4144 6590 7880 14990
    35 Br bromine 1139.9 2103 3470 4560 5760 8550 9940 18600
    36 Kr krypton 1350.8 2350.4 3565 5070 6240 7570 10710 12138 22274 25880
    37 Rb rubidium 403.0 2633 3860 5080 6850 8140 9570 13120 14500 26740
    38 Sr strontium 549.5 1064.2 4138 5500 6910 8760 10230 11800 15600 17100
    39 Y yttrium 600 1180 1980 5847 7430 8970 11190 12450 14110 18400
    40 Zr zirconium 640.1 1270 2218 3313 7752 9500
    41 Nb niobium 652.1 1380 2416 3700 4877 9847 12100
    42 Mo molybdenum 684.3 1560 2618 4480 5257 6640.8 12125 13860 15835 17980
    43 Tc technetium 702 1470 2850
    44 Ru ruthenium 710.2 1620 2747
    45 Rh rhodium 719.7 1740 2997
    46 Pd palladium 804.4 1870 3177
    47 Ag silver 731.0 2070 3361
    48 Cd cadmium 867.8 1631.4 3616
    49 In indium 558.3 1820.7 2704 5210
    50 Sn tin 708.6 1411.8 2943.0 3930.3 7456
    51 Sb antimony 834 1594.9 2440 4260 5400 10400
    52 Te tellurium 869.3 1790 2698 3610 5668 6820 13200
    53 I iodine 1008.4 1845.9 3180
    54 Xe xenon 1170.4 2046.4 3099.4
    55 Cs caesium 375.7 2234.3 3400
    56 Ba barium 502.9 965.2 3600
    57 La lanthanum 538.1 1067 1850.3 4819 5940
    58 Ce cerium 534.4 1050 1949 3547 6325 7490
    59 Pr praseodymium 527 1020 2086 3761 5551
    60 Nd neodymium 533.1 1040 2130 3900
    61 Pm promethium 540 1050 2150 3970
    62 Sm samarium 544.5 1070 2260 3990
    63 Eu europium 547.1 1085 2404 4120
    64 Gd gadolinium 593.4 1170 1990 4250
    65 Tb terbium 565.8 1110 2114 3839
    66 Dy dysprosium 573.0 1130 2200 3990
    67 Ho holmium 581.0 1140 2204 4100
    68 Er erbium 589.3 1150 2194 4120
    69 Tm thulium 596.7 1160 2285 4120
    70 Yb ytterbium 603.4 1174.8 2417 4203
    71 Lu lutetium 523.5 1340 2022.3 4370 6445
    72 Hf hafnium 658.5 1440 2250 3216
    73 Ta tantalum 761 1500
    74 W tungsten 770 1700
    75 Re rhenium 760 1260 2510 3640
    76 Os osmium 840 1600
    77 Ir iridium 880 1600
    78 Pt platinum 870 1791
    79 Au gold 890.1 1980
    80 Hg mercury 1007.1 1810 3300
    81 Tl thallium 589.4 1971 2878
    82 Pb lead 715.6 1450.5 3081.5 4083 6640
    83 Bi bismuth 703 1610 2466 4370 5400 8520
    84 Po polonium 812.1
    85 At astatine 899.003
    86 Rn radon 1037
    87 Fr francium 380
    88 Ra radium 509.3 979.0
    89 Ac actinium 499 1170 1900 4700
    90 Th thorium 587 1110 1978 2780
    91 Pa protactinium 568 1128 2991
    92 U uranium 597.6 1420 1900 3145
    93 Np neptunium 604.5 1128 1997 3242
    94 Pu plutonium 584.7 1128 2084 3338
    95 Am americium 578 1158 2132 3493
    96 Cm curium 581 1196 2026 3550
    97 Bk berkelium 601 1186 2152 3434
    98 Cf californium 608 1206 2267 3599
    99 Es einsteinium 619 1216 2334 3734
    100 Fm fermium 627 1225 2363 3792
    101 Md mendelevium 635 1235 2470 3840
    102 No nobelium 642 1254 2643 3956
    103 Lr lawrencium 470 1428 2228 4910
    104 Rf rutherfordium 579.9 1389.4 2296.4 3077.9
    105 Db dubnium 664.8 1546.7 2378.4 3298.8 4305.2
    106 Sg seaborgium 757.4 1732.9 2483.5 3415.6 4561.8 5715.8
    107 Bh bohrium 742.9 1688.5 2566.5 3598.9 4727.8 5991.7 7226.8
    108 Hs hassium 733.3 1756.0 2827.0 3637.5 4940.0 6175.1 7535.5 8857.4
    109 Mt meitnerium 800.8 1823.6 2904.2 3859.4 4920.8
    110 Ds darmstadtium 955.2 1891.1 3029.6 3955.9 5113.7
    111 Rg roentgenium 1022.7 2074.4 3077.9 4052.4 5306.7
    112 Cn copernicium 1154.9 2170.0 3164.7 4245.4 5499.7
    113 Uut ununtrium 704.9 2238.5 3023.3 4351.5 5692.6
    114 Fl flerovium 823.9 1601.6 3367.3 4399.7 5847.0
    115 Uup ununpentium 538.4 1756.0 2653.3 4679.5 5721.6
    116 Lv livermorium 723.6 1331.5 2846.3 3811.2 6078.6
    117 Uus ununseptium 742.9 1785.0–1920.1
    118 Uuo ununoctium 839.4 1563.1
    119 Uue ununennium 463.1 1698.1
    120 Ubn unbinilium 578.9 895.4–918.5
    121 Ubu unbiunium 429.4