Question

The energy of electron in the ground state of hydrogen atom is -13.6 eV. The energy required for the transition from $n=2$ to $n=3$ will be

• A. $2eV$
• B. $4eV$
• C. $1.89eV$
• D. $2.89eV$

Answer 1

Answer: (C)

$1.89eV$

Energy in the $n^{th}$ shell of Hydrogen atom $=-E_n\left(\frac{1}{n^2}\right)$ where $E_n=-13.6eV$

Energy required for transition from $n=2$ to $n=3$
$E_n[\frac{1}{n_1^2}-\frac{1}{n_2^2}]=13.6[\frac{1}{4}-\frac{1}{9}]=\frac{5}{36}\times 13.6eV$$=1.889eV\approx 1.89eV$