Question

Ionisation energy of a hydrogen like species is $54.4 \,eV$. Calculate radius of second bohr orbit of this species.

• A. $0.529\,\mathring{A}$
• B. $1.058\,\mathring{A}$
• C. $2.116\,\mathring{A}$
• D. $2.106\,\mathring{A}$

Answer 1

Answer: (B)

Ionisation energy $13.6 \times z^{2}=54.4$
$\therefore Z =2$
$r =0.529 \frac{ n ^{2}}{ z } \mathring{A}=0.529\times \frac{2^{2}}{2}=1.058\,\mathring{A}$