Question

Calculate the energy required for the process He+ (g)$\rightarrow$He2+ (g) + e– The ionization energy for the H atom in the ground state is 2.18 × 10–18 J atom–1

Answer 1

Energy associated with hydrogen-like species is given by,
En = - 2.18 × 10 -18 ($\frac{Z^2}{n^2}$) J
For the ground state of the hydrogen atom,
ΔE = E∞ - E1
= 0 - [- 2.18 × 10 - 18 {$\frac{(1)^2}{(1)^2}$}] J
ΔE = - 2.18 × 10-18 J
For the given process,
He+ (g)$\rightarrow$ He2+ (g) + e-
An electron is removed from n = 1 to n = ∞.
ΔE = E∞ - E1
= 0 - [- 2.18 × 10-18 {$\frac{(2)^2}{(1)^2}$]
ΔE = 8.72 × 10-18 J
∴ The energy required for the process is 8.72 × 10-8 J.