Question

If the radius of the first Bohr orbit of the H atom is r then for the Li²⁺ ion it will be –

• A. 3r
• B. 9r
• C. r/3
• D. r/9

Answer 1

Answer: (C)

r/3

Answer 2

Q = r µ $\frac{n^{2}}{Z}$ \ $\frac{r_{H}}{r_{Li^{2 +}}}$ = $\frac{Z_{Li}}{Z_{H}}$

̃ $r_{Li^{2 +}}$ = r_H × $\frac{Z_{H}}{Z_{Li}}$ = $\frac{r}{3}$