Question

If $E$ is the energy of electron in $n^{th}$ orbit of hydrogen atom, then the energy of electron in $n^{th}$ orbit of ${\text{He}}^{+}$ will be

• A. $E$
• B. $2E$
• C. $4E$
• D. $8E$

Answer 1

The correct option is C $4E$

Using energy equation for $n^{th}$ orbit,

$E_n=\frac{Z^2}{n^2}\left(13.6\text{eV}\right)$

Therefore, for ${\text{He}}^{+}$ ion,

$E_n=2^{2}E=4E$