The energy of a hydrogen atom in its ground state is -13.6 eV. What is the quantum number of the orbit corresponding to the energy level of -0.85 eV?

Options

A. 2
B. 3
C. 4
D. 5

Answer

C

Explanation

`E_n = - (13.6)/(n^2) therefore -0.85 = - (13.6)/(n^2)`
`n^2 = (13.6)/(0.85) = 16 therefore n=4`