View source for Data:Ionization energies of the elements (Z = 1–30)

{{see|Ionization energy}}
{| class="wikitable sortable"
|-
! rowspan=2 | [[Atomic number|''Z'']]
! rowspan=2 | Element
! colspan=13 | [[Ionization energy]]/[[Electronvolt|eV]]
|-
! I
! II
! III
! IV
! V
! VI
! VII
! VIII
! IX
! X
! XI
! XII
! XIII
|-
| 1
| [[Hydrogen]]
| 13.598
| colspan=12 | 
|-
| 2
| [[Helium]]
| 24.587
| 54.416
| colspan=11 | 
|-
| 3
| [[Lithium]]
| 5.392
| 75.638
| 122.451
| colspan=10 | 
|-
| 4
| [[Beryllium]]
| 9.322
| 18.211
| 155.893
| 217.713
| colspan=9 | 
|-
| 5
| [[Boron]]
| 8.298
| 25.154
| 37.930
| 259.368
| 340.217
| colspan=8 | 
|-
| 6
| [[Carbon]]
| 11.260
| 24.383
| 47.887
| 64.492
| 392.077
| 489.981
| colspan=7 | 
|-
| 7
| [[Nitrogen]]
| 14.534
| 29.601
| 47.448
| 77.472
| 97.888
| 352.057
| 667.029
| colspan=6 | 
|-
| 8
| [[Oxygen]]
| 13.618
| 35.116
| 54.934
| 77.412
| 113.896
| 138.116
| 739.315
| 871.387
| colspan=5 | 
|-
| 9
| [[Fluorine]]
| 17.422
| 34.970
| 62.707
| 87.138
| 114.240
| 157.161
| 185.182
| 953.886
| 1103.089
| colspan=4 |
|-
| 10
| [[Neon]]
| 21.564
| 40.962
| 63.45
| 97.11
| 126.21
| 157.93
| 207.27
| 239.09
| 1195.797
| 1362.164
| colspan=3 |
|-
| 11
| [[Sodium]]
| 5.139
| 47.286
| 71.64
| 98.91
| 138.39
| 172.15
| 208.47
| 264.18
| 299.87
| 1465.091
| 1648.659
| colspan=2 |
|-
| 12
| [[Magnesium]]
| 7.646
| 15.035
| 80.143
| 109.24
| 141.26
| 186.50
| 224.94
| 265.90
| 327.95
| 367.53
| 1761.802
| 1962.613
| 
|-
| 13
| [[Aluminium]]
| 5.986
| 18.828
| 28.447
| 119.99
| 153.71
| 190.47
| 241.43
| 284.59
| 330.21
| 398.57
| 442.07
| 2085.983
| 2304.080
|-
| 14
| [[Silicon]]
| 8.151
| 16.345
| 33.492
| 45.141
| 166.77
| 205.05
| 246.52
| 303.17
| 351.10
| 401.43
| 476.06
| 523.50
| 2437.676
|-
| 15
| [[Phosphorus]]
| 10.486
| 19.725
| 30.18
| 51.37
| 65.023
| 220.43
| 263.22
| 390.41
| 371.73
| 424.50
| 479.57
| 560.41
| 611.85
|-
| 16
| [[Sulfur]]
| 10.360
| 23.33
| 34.83
| 47.30
| 72.68
| 88.049
| 280.93
| 328.23
| 379.10
| 447.09
| 504.78
| 564.65
| 651.63
|-
| 17
| [[Chlorine]]
| 12.967
| 23.81
| 39.61
| 53.46
| 67.8
| 97.03
| 114.193
| 348.28
| 400.05
| 455.62
| 529.26
| 591.97
| 656.69
|-
| 18
| [[Argon]]
| 15.759
| 27.629
| 40.74
| 59.81
| 75.02
| 91.007
| 124.319
| 143.456
| 422.44
| 478.68
| 538.95
| 618.24
| 686.09
|-
| 19
| [[Potassium]]
| 4.341
| 31.625
| 45.72
| 60.91
| 82.66
| 100.0
| 117.56
| 154.86
| 175.814
| 503.44
| 564.13
| 629.09
| 714.02
|-
| 20
| [[Calcium]]
| 6.113
| 11.871
| 50.908
| 67.10
| 84.41
| 108.78
| 127.7
| 147.24
| 188.54
| 211.270
| 591.25
| 656.39
| 726.03
|-
| 21
| [[Scandium]]
| 6.54
| 12.80
| 24.76
| 73.47
| 91.66
| 111.1
| 138.0
| 158.7
| 180.02
| 225.32
| 249.832
| 685.89
| 755.47
|-
| 22
| [[Titanium]]
| 6.82
| 13.58
| 27.491
| 43.266
| 99.22
| 119.36
| 140.8
| 168.5
| 193.2
| 215.91
| 265.23
| 291.497
| 787.33
|-
| 23
| [[Vanadium]]
| 6.74
| 14.65
| 29.310
| 46.707
| 65.23
| 128.12
| 150.17
| 173.7
| 205.8
| 230.5
| 255.04
| 308.25
| 336.267
|-
| 24
| [[Chromium]]
| 6.766
| 16.50
| 30.96
| 49.1
| 69.3
| 90.56
| 161.1
| 184.7
| 209.3
| 244.4
| 270.8
| 298.0
| 355
|-
| 25
| [[Manganese]]
| 7.435
| 15.640
| 33.667
| 51.2
| 72.4
| 95
| 119.27
| 196.46
| 221.8
| 243.3
| 286.0
| 314.4
| 343.6
|-
| 26
| [[Iron]]
| 7.870
| 16.18
| 30.651
| 54.8
| 75.0
| 99
| 125
| 151.06
| 235.04
| 262.1
| 290.4
| 330.8
| 361.0
|-
| 27
| [[Cobalt]]
| 7.86
| 17.06
| 33.50
| 51.3
| 79.5
| 102
| 129
| 157
| 186.13
| 276
| 305
| 336
| 379
|-
| 28
| [[Nickel]]
| 7.635
| 18.168
| 35.17
| 54.9
| 75.5
| 108
| 133
| 162
| 193
| 224.5
| 321.2
| 352
| 384
|-
| 29
| [[Copper]]
| 7.726
| 20.292
| 36.83
| 55.2
| 79.9
| 103
| 139
| 166
| 199
| 232
| 266
| 368.8
| 401
|-
| 30
| [[Zinc]]
| 9.394
| 17.964
| 39.722
| 59.4
| 82.6
| 108
| 134
| 174
| 203
| 238
| 274
| 310.8
| 419.7
|-
|}

==References==
{{NSRDS-NBS 34}}.

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