Q22 / 155 · WBJEE 2024 · Chemistry
Which hydrogen like species will have the same radius as that of $1^{\text {st }}$ Bohr orbit of hydrogen atom?
- A$\mathrm{n}=2, \mathrm{Li}^{2+}$
- Correct answerB$\mathrm{n}=2, \mathrm{Be}^{3+}$
- C$\mathrm{n}=2, \mathrm{He}^{+}$
- D$\mathrm{n}=3, \mathrm{Li}^{2+}$
Solution
Hint : Radius of $n^{\text {th }}$ orbit $=0.529 \frac{n^2}{Z} Ã…$
Radius of $1^{\text {st }}$ Bohr Orbit of Hydrogen atom $=0.529 \times \frac{1^2}{1}=0.529 Ã…$
Radius of $2^{\text {nd }}$ Bohr Orbit of $\mathrm{Be}^{3+}=0.529 \frac{2^2}{4}=0.529 Ã…$
Hence, the correct answer is option: 'B'.