Q6 / 60 · KVPY 2011 (SA) · Chemistry
The set of principal (n), azimuthal $(\ell)$ and magnetic $\left(\mathrm{m}_{1}\right)$ quantum numbers that is not allowed for the electron in $\mathrm{H}$-atom is
- A$\mathrm{n}=3, \ell=1, \mathrm{~m}_{1}=-1$
- B$\mathrm{n}=3, \ell=0, \mathrm{~m}_{1}=0$
- C$\mathrm{n}=2, \ell=1, \mathrm{~m}_{1}=0$
- Correct answerD$\mathrm{n}=2, \ell=2, \mathrm{~m}_{1}=-1$
Solution
$n$ is always greater than $\ell$
and $\mathrm{m}=-\ell \ldots \ldots .0 \ldots \ldots .+\ell$
If $n=2$, then $\ell=0,1$
and $\mathrm{m}_{\ell}=0,\{-1,0,+1\}$
Hence, the correct answer is option: 'D'.