Question

The total energy of the electron in the hydrogen atom in the ground state is -13.6 eV. Which of the following is its kinetic energy in the first excited state?

• A. 13.6 eV
• B. 6.8 eV
• C. 3.4 eV
• D. 1.825 eV

Answer 1

The correct option is C 3.4 eV

Total energy of electron in ground state $E=-13.6eV$
Total energy in the first excited state $E_1=\frac{-13.6}{2^2}=-3.4eV$
Kinetic energy of electron in first excited state $K_1=|E_1|=3.4eV$