Question

The radius of hydrogen atom in the ground state is 0.53 Å. The radius of Li²⁺ ion (atomic number = 3) in a similar state is

(a) 0.17 Å

(b) 1.06  A

(c) 0.53 Å

(d) 0.265 Å

Answer 1

Correct option is (a) 0.17 Å

\(r_n = \frac {n^2}Z .a_0\)

\(= \frac{0.53}{3}\)

\(= 0.17 \) Å

[n = 1, Z = 3]