The ionisation energy of H atom is `13.6 ` eV. What will be the ionisation energy of `He^(o+)` and `Li^(2+)` ions ?

Answer

A, B, D

Explanation

IE of an ion = IE of H atom `xx Z^(2)`
`IE of He^(o+) = 13.6 eV xx 2^(2) = 54.4 eV`
`IE of Li^(2+) = 13.6 eV xx 3^(2) = 122.4 eV`