# Homework Help: Energy of an electron in hydrogen!

1. Oct 24, 2012

### mahrap

What is the energy of an electron in the 2s orbital of a hydrogen atom?

I thought En = -RZ^2 / n^2

Why am i not getting the right answer with

Z = 1
n = 2
and R just the value of the constant

2. Oct 25, 2012

### AGNuke

$$E = -13.6 \frac{z^2}{n^2}eV$$

3. Oct 25, 2012

### Redbelly98

Staff Emeritus
If you don't tell us what answer you got, it is difficult to say why it is wrong.