Q26 / 90 · KVPY 2011 (SB/SX) · Chemistry
The electron in hydrogen atom is in the first Bohr orbit $(\mathrm{n}=1$ ). The ratio of transition energies, $\mathrm{E}(\mathrm{n}=1 \rightarrow \mathrm{n}$ $=3$ ) to $\mathrm{E}(\mathrm{n}=1 \rightarrow \mathrm{n}=2$ ), is-
- Correct answerA$32 / 27$
- B$16 / 27$
- C$32 / 9$
- D$8 / 9$
Solution
$\Delta \mathrm{E}=13.6\left(\frac{1}{\mathrm{n}_{1}^{2}}-\frac{1}{\mathrm{n}_{2}^{2}}\right) \mathrm{eV} / \mathrm{atom}$
$\Delta \mathrm{E}_{1 \rightarrow 3}=\frac{\frac{1}{1^{2}}-\frac{1}{3^{2}}}{\frac{1}{1^{2}}-\frac{1}{2^{2}}}=\frac{.32}{27}$
${\Delta \mathrm{E}_{1 \rightarrow 2}}$
Hence, the correct answer is option: 'A'.