# Energy required to ionize a hydrogen atom from n=1

1. Feb 22, 2005

### tony873004

We were given this formula in class:

$$delta E= chR (\frac{1}{1^2} - \frac{1}{inf})$$

the $$1/1^2$$ is because it is in ground state. So the formula simplifies to
$$chR$$

c = 299792000
h = 6.626E-34
R = 10970000

and $$1.60217653*10^{19} Joules / eV$$

I get:
$$1.36009026784583 * 10^{-37} eV$$

The teacher did it in class and got 13.6 eV

Same answer, just 38 magnitudes off

What am I doing wrong?

** edit ** I figured it out. It's not 19, its -19 for Joules to eV

Last edited: Feb 22, 2005
2. Feb 23, 2005

### dextercioby

There you go:you have scientifically proven that $10^{-19}$ and $10^{19}$ are 38 orders of magnitude apart.Congratulations!!

Daniel.