Input interpretation
helium hydrogen | atomic radius
Results
helium | 31 pm (picometers) hydrogen | 25 pm (picometers)
Relative values
| visual | ratios | | comparisons hydrogen | | 0.8 | 1 | 19% smaller helium | | 1 | 1.2 | 24% larger
Plot
Plot
Periodic table location
Periodic table location
Atomic radii properties
| helium | hydrogen atomic radius (empirical) | | 25 pm atomic radius (calculated) | 31 pm | 53 pm covalent radius | 28 pm | 31 pm van der Waals radius | 140 pm | 120 pm
Units
