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A6: Atomic Ionization Energies

  • Page ID
    11260
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    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.

    At#

    sym 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th
    1 H 1312.  
    2 He 2372.3 5250.5
    3 Li 520.2 7298.1 11815.0
    4 Be 899.5 1757.1 14848.7 21006.6
    5 B 800.6 2427.1 3659.7 25025.8 32826.7
    6 C 1086.5 2352.6 4620.5 6222.7 37831 47277.0
    7 N 1402.3 2856 4578.1 7475.0 9444.9 53266.6 64360
    8 O 1313.9 3388.3 5300.5 7469.2 10989.5 13326.5 71330 84078.0
    9 F 1681.0 3374.2 6050.4 8407.7 11022.7 15164.1 17868 92038.1 106434.3
    10 Ne 2080.7 3952.3 6122 9371 12177 15238 19999.0 23069.5 115379.5 131432
    11 Na 495.8 4562 6910.3 9543 13354 16613 20117 25496 28932 141362
    12 Mg 737.7 1450.7 7732.7 10542.5 13630 18020 21711 25661 31653 35458
    13 Al 577.5 1816.7 2744.8 11577 14842 18379 23326 27465 31853 38473
    14 Si 786.5 1577.1 3231.6 4355.5 16091 19805 23780 29287 33878 38726
    15 P 1011.8 1907 2914.1 4963.6 6273.9 21267 25431 29872 35905 40950
    16 S 999.6 2252 3357 4556 7004.3 8495.8 27107 31719 36621 43177
    17 Cl 1251.2 2298 3822 5158.6 6542 9362 11018 33604 38600 43961
    18 Ar 1520.6 2665.8 3931 5771 7238 8781 11995 13842 40760 46186
    19 K 418.8 3052 4420 5877 7975 9590 11343 14944 16963.7 48610
    20 Ca 589.8 1145.4 4912.4 6491 8153 10496 12270 14206 18191 20385
    21 Sc 633.1 1235.0 2388.6 7090.6 8843 10679 13310 15250 17370 21726
    22 Ti 658.8 1309.8 2652.5 4174.6 9581 11533 13590 16440 18530 20833
    23 V 650.9 1414 2830 4507 6298.7 12363 14530 16730 19860 22240
    24 Cr 652.9 1590.6 2987 4743 6702 8744.9 15455 17820 20190 23580
    25 Mn 717.3 1509.0 3248 4940 6990 9220 11500 18770 21400 23960
    26 Fe 762.5 1561.9 2957 5290 7240 9560 12060 14580 22540 25290
    27 Co 760.4 1648 3232 4950 7670 9840 12440 15230 17959 26570
    28 Ni 737.1 1753.0 3395 5300 7339 10400 12800 15600 18600 21670
    29 Cu 745.5 1957.9 3555 5536 7700 9900 13400 16000 19200 22400
    30 Zn 906.4 1733.3 3833 5731 7970 10400 12900 16800 19600 23000
    31 Ga 578.8 1979.3 2963 6180
    32 Ge 762 1537.5 3302.1 4411 9020
    33 As 947.0 1798 2735 4837 6043 12310
    34 Se 941.0 2045 2973.7 4144 6590 7880 14990
    35 Br 1139.9 2103 3470 4560 5760 8550 9940 18600
    36 Kr 1350.8 2350.4 3565 5070 6240 7570 10710 12138 22274 25880
    37 Rb 403.0 2633 3860 5080 6850 8140 9570 13120 14500 26740
    38 Sr 549.5 1064.2 4138 5500 6910 8760 10230 11800 15600 17100
    39 Y 600 1180 1980 5847 7430 8970 11190 12450 14110 18400
    40 Zr 640.1 1270 2218 3313 7752 9500
    41 Nb 652.1 1380 2416 3700 4877 9847 12100
    42 Mo 684.3 1560 2618 4480 5257 6640.8 12125 13860 15835 17980
    43 Tc 702 1470 2850
    44 Ru 710.2 1620 2747
    45 Rh 719.7 1740 2997
    46 Pd 804.4 1870 3177
    47 Ag 731.0 2070 3361
    48 Cd 867.8 1631.4 3616
    49 In 558.3 1820.7 2704 5210
    50 Sn 708.6 1411.8 2943.0 3930.3 7456
    51 Sb 834 1594.9 2440 4260 5400 10400
    52 Te 869.3 1790 2698 3610 5668 6820 13200
    53 I 1008.4 1845.9 3180
    54 Xe 1170.4 2046.4 3099.4
    55 Cs 375.7 2234.3 3400
    56 Ba 502.9 965.2 3600
    57 La 538.1 1067 1850.3 4819 5940
    58 Ce 534.4 1050 1949 3547 6325 7490
    59 Pr 527 1020 2086 3761 5551
    60 Nd 533.1 1040 2130 3900
    61 Pm 540 1050 2150 3970
    62 Sm 544.5 1070 2260 3990
    63 Eu 547.1 1085 2404 4120
    64 Gd 593.4 1170 1990 4250
    65 Tb 565.8 1110 2114 3839
    66 Dy 573.0 1130 2200 3990
    67 Ho 581.0 1140 2204 4100
    68 Er 589.3 1150 2194 4120
    69 Tm 596.7 1160 2285 4120
    70 Yb 603.4 1174.8 2417 4203
    71 Lu 523.5 1340 2022.3 4370 6445
    72 Hf 658.5 1440 2250 3216
    73 Ta 761 1500
    74 W 770 1700
    75 Re 760 1260 2510 3640
    76 Os 840 1600
    77 Ir 880 1600
    78 Pt 870 1791
    79 Au 890.1 1980
    80 Hg 1007.1 1810 3300
    81 Tl 589.4 1971 2878
    82 Pb 715.6 1450.5 3081.5 4083 6640
    83 Bi 703 1610 2466 4370 5400 8520
    84 Po 812.1
    85 At 899.003
    86 Rn 1037
    87 Fr 380
    88 Ra 509.3 979.0
    89 Ac 499 1170 1900 4700
    90 Th 587 1110 1978 2780
    91 Pa 568 1128   2991
    92 U 597.6 1420 1900 3145
    93 Np 604.5 1128 1997 3242
    94 Pu 584.7 1128 2084 3338
    95 Am 578 1158 2132 3493
    96 Cm 581 1196 2026 3550
    97 Bk 601 1186 2152 3434
    98 Cf 608 1206 2267 3599
    99 Es 619 1216 2334 3734
    100 Fm 627 1225 2363 3792
    101 Md 635 1235 2470 3840
    102 No 642 1254 2643 3956
    103 Lr 470 1428 2228 4910
    104 Rf 579.9 1389.4 2296.4 3077.9
    105 Db 664.8 1546.7 2378.4 3298.8 4305.2
    106 Sg 757.4 1732.9 2483.5 3415.6 4561.8 5715.8
    107 Bh 742.9 1688.5 2566.5 3598.9 4727.8 5991.7 7226.8
    108 Hs 733.3 1756.0 2827.0 3637.5 4940.0 6175.1 7535.5 8857.4
    109 Mt 800.8 1823.6 2904.2 3859.4 4920.8
    110 Ds 955.2 1891.1 3029.6 3955.9 5113.7
    111 Rg 1022.7 2074.4 3077.9 4052.4 5306.7
    112 Cn 1154.9 2170.0 3164.7 4245.4 5499.7
    113 Uut 704.9 2238.5 3023.3 4351.5 5692.6
    114 Fl 823.9 1601.6 3367.3 4399.7 5847.0
    115 Uup 538.4 1756.0 2653.3 4679.5 5721.6
    116 Lv 723.6 1331.5 2846.3 3811.2 6078.6
    117 Uus 742.9 1785.0–1920.1
    118 Uuo 839.4 1563.1
    119 Uue 463.1 1698.1
    120 Ubn 578.9 895.4–918.5
    121 Ubu 429.4


    A6: Atomic Ionization Energies is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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