Calculate the energy required for the process
` He^(+)(g) to He^(2+) (g) + e^(-)`
The ionization energy for the H atom in the ground state is `2.18xx10^(-18) J "atom" ^(-1)`

Answer

`E_(1)` for `H` atom `=-1.E.=-2.18xx10^(-18) J`
`E_(1)` for `He^(+)=E_(1(H))xxZ^(2)=-2.18xx10^(-18)xx2^(2)J=-8.72xx10^(-18)J`
The given process represents ionization of `He^(+)`.
The energy required for ionization of `He^(+)=E_(1(He^(+)))=8.72xx10^(-18) J`