Input interpretation
halogens | first ionization energy
Summary
median | 1139.9 kJ/mol highest | 1681 kJ/mol (fluorine) lowest | 920 kJ/mol (astatine) distribution | | (based on 5 values; 1 unavailable)
Entity with missing value
tennessine
Ranked values
| | visual | ratios | 5 | astatine | | 0.547 | 1 4 | iodine | | 0.5999 | 1.1 3 | bromine | | 0.6781 | 1.24 2 | chlorine | | 0.7443 | 1.36 1 | fluorine | | 1 | 1.83
Plot
Plot
Periodic table location
Periodic table location
First ionization energy rankings
1 | astatine | 920 kJ/mol 2 | iodine | 1008.4 kJ/mol 3 | bromine | 1139.9 kJ/mol 4 | chlorine | 1251.2 kJ/mol 5 | fluorine | 1681 kJ/mol (based on 5 values; 1 unavailable)
Unit conversions for median first ionization energy 1139.9 kJ/mol
1.1399 MJ/mol (megajoules per mole)
1.1399×10^6 J/mol (joules per mole)
272.44 kcal/mol (thermochemical kilocalories per mole)
11.814 eV (molar electronvolts)
Comparisons for median first ionization energy 1139.9 kJ/mol
≈ 0.48 × molar energy required to remove the first electron from helium ( 2372 kJ/mol )
≈ 3 × molar energy required to remove the first electron from cesium ( 377 kJ/mol )