- #1

member 659869

$$E_{mol of electrons} = \frac{-1312kJ}{n^2}$$

where $n$ is in electron shell number

But when we divide by 1 mol to get the energy value for each electron we get

$$E_{electron} = \frac{-2.178 \cdot 10^{-18}}{n^2} J$$

but the actual equation is (as given by textbook) rather

$$E_{electron} = \frac{-2.178 \cdot 10^{-18} \cdot Z^2}{n^2} J$$

Where $Z$ is nuclear charge. Why must we introduce $Z$ and why is it not used in the first equation?