Question

Supposing the energy of fourth shell for hydrogen atom is $-50$ a.u (arbitrary unit). What would be its ionization potential?

• A. $50$
• B. $800$
• C. $15.4$
• D. $20.8$

Answer 1

The correct option is B $800$

We know,

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

By this equation we can say that,

Energy of the first shell is 16 times of the fourth shell.

So,energy of first shell should be - 800 au.

Hence IP of H atom will be +800 au.