Question

Angular momentum of an electron having energy -0.85 eV in hydrogen atom, will be

• A. $h/2\pi$
• B. $h/\pi$
• C. $2h/\pi$
• D. $3h/\pi$

Answer 1

The correct option is C $2h/\pi$

$\begin{array}{c}\text{Given - * Energy of electron}=-0.85ev\text{.}\\ \text{we Rnow that Energy of electoon is given by -}\\ E=-13.6\cdot \left(\frac{1}{n^2}\right)eVn\to \text{principal quantum num}\end{array}$

$\begin{array}{c}\Rightarrow \frac{-13\cdot 6}{n^2}=-0.85\\ \Rightarrow n^2=\frac{13\cdot 6}{0.85}=16\\ \text{Henu, by Bohr quantization of angular momentum-}\\ \begin{array}{cc}& =\frac{nh}{2\pi }\\ \text{for}n=4\text{we get}& \\ L=\frac{2h}{\pi }& \end{array}\end{array}$