Question

What is the seperation energy (in eV) for $B{e}^{3+}$ in the first excited state in eV?

• A. $13.6\text{eV}$
• B. $27.2\text{eV}$
• C. $40.8\text{eV}$
• D. $54.4\text{eV}$

Answer 1

The correct option is D $54.4\text{eV}$

Separation energy is the energy required to remove an electron from the given state to infinity. It the energy difference between the given state and infinity.
$ForB{e}^{3+}\text{By using formula}{E}_{\infty }-E_2=+13.6\frac{z^2}{n^2}$
$=13.6\times \frac{4^2}{2^2}=54.4eV$