Question

The energy of ground electronic state of hydrogen atom is $-13.4eV$. The energy of the first excited state will be

• A. $-54.4eV$
• B. $-27.2eV$
• C. $-6.8eV$
• D. $-3.4eV$

Answer 1

The correct option is D $-3.4eV$

Ground state means $n=1$

and first excited state means second state means $n=2$

As $Energy\propto 1/n^2$

So energy for $n=2$ will be $E_1/2^2=E_1/4=-13.6/4=-3.4eV$

Option D is correct