Question

In a mixture of $H-H{e}^{+}$ gas, H atom and $H{e}^{+}$ ions are excited to their respective first excited states. Subsequently, H atoms transfer its excitation energy to $H{e}^{+}$ ions by collision. Assuming that Bohr model of an atom is applicable, the quantum number n of the statement finally populated in $H{e}^{+}$ ion will be________.

• A. 1
• B. 2
• C. 4
• D. 6

Answer 1

Answer: (C)

4

In $H_{1\to 2}$ the excitation energy = 10.2 eV
When H atoms transfer their excitation energy (10.2 eV) to the electron in $H{e}^{\oplus }$ is further excited to say $n=n_2$,
thus $10.2=13.6\times 2^2\times \left(1/2^2-1/n_2^2\right)$,
$\therefore$ $n_2=4$

Hence, the correct option is $\left(C\right)$.