The total energy of eletcron in the ground state of hydrogen atom is `-13.6 eV`. The kinetic enegry of an electron in the first excited state is

Options

A. 3.4 eV
B. 6.8 eV
C. 13.6 eV
D. 1.7 eV

Answer

A

Explanation

The energy of hydrogen atom when the electron revolves in nth orbit is
`E=(-13.6)/(n^(2))eV`
In the ground state, `n=1`
`therefore E=(-13.6)/(1^(2))=-13.6eV`
For `n=2,E=(-13.6)/(2^(2))=-3.4eV`
So, kinetic energy of electron in the first excited state (i.e., for n=2) is
`K=-E=-(-3.4)=3.4eV`