Question

What would be the radius of second orbit of ${He}^{+}$ ion?

• A. $1.058\mathring{A}$
• B. $3.023\mathring{A}$
• C. $2.068\mathring{A}$
• D. $4.458\mathring{A}$

Answer 1

Answer: (A)

Radius of the nth orbit, $r_n=0.529\frac{n^2}{Z}$ $A^o$

For $H{e}^{+}$ ion, $Z=2$

Radius of 2nd orbit, $r_2=0.529\frac{2^2}{2}$

$⟹r_2=1.058$ $\mathring{A}$