Question

The total energy of the electron in the hydrogen atom in the ground state is $-13.6eV$. The kinetic energy of this electron is

• A. $+13.6eV$
• B. $0$
• C. $-13.6eV$
• D. $+6.8eV$

Answer 1

The correct option is A $+13.6eV$

Kinetic energy of electron $=\frac{kz{e}^2}{2r}$

Potential energy of electron $=-\frac{kz{e}^2}{r}$

$P.E=-2(K.E)$

Total energy $=P.E+K.E$

$=-K.E$

Total energy in first excited state $=-13.6eV$

$K.E=-(-13.6eV)$

$K.E=13.6eV$

$\therefore$ option A is correct.