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

Given:

Ionization energy of hydrogen atom (ground state),
E_H = 2.18 × 10⁻¹⁸ J atom⁻¹

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Step 1: Use relation for hydrogen-like species

For hydrogen-like ions,

Ionization energy ∝ Z²

E = Z² × E_H

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Step 2: Apply for He⁺ ion

For He⁺, atomic number Z = 2

E = (2)² × 2.18 × 10⁻¹⁸

E = 4 × 2.18 × 10⁻¹⁸

E = 8.72 × 10⁻¹⁸ J atom⁻¹

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Final Answer:

Energy required for the process
He⁺(g) → He²⁺(g) + e⁻

= 8.72 × 10⁻¹⁸ J atom⁻¹