Input interpretation
alkali metals | first ionization energy
Summary
median | 410.9 kJ/mol highest | 520.2 kJ/mol (lithium) lowest | 375.7 kJ/mol (cesium) distribution |
Units
Ranked values
| | visual | ratios | 6 | cesium | | 0.722 | 1 5 | francium | | 0.73 | 1.01 4 | rubidium | | 0.775 | 1.073 3 | potassium | | 0.805 | 1.115 2 | sodium | | 0.953 | 1.32 1 | lithium | | 1 | 1.385
Plot
Plot
Periodic table location
Periodic table location
First ionization energy rankings
1 | cesium | 375.7 kJ/mol 2 | francium | 380 kJ/mol 3 | rubidium | 403 kJ/mol 4 | potassium | 418.8 kJ/mol 5 | sodium | 495.8 kJ/mol 6 | lithium | 520.2 kJ/mol
Unit conversions for median first ionization energy 410.9 kJ/mol
0.4109 MJ/mol (megajoules per mole)
410900 J/mol (joules per mole)
98.21 kcal/mol (thermochemical kilocalories per mole)
98210 cal/mol (calories per mole)
4.259 eV (molar electronvolts)
Comparisons for median first ionization energy 410.9 kJ/mol
≈ ( 0.17 ≈ 1/6 ) × molar energy required to remove the first electron from helium ( 2372 kJ/mol )
≈ 1.1 × molar energy required to remove the first electron from cesium ( 377 kJ/mol )