# What are the quantum numbers for the last electron in zinc?

Nov 4, 2015

$\left(4 , 0 , 0 , + \frac{1}{2}\right)$ or $\left(4 , 0 , 0 , - \frac{1}{2}\right)$

#### Explanation:

The electron configuration of Zinc is:

""_30Zn: 1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(2)3d^(10)

The quantum number of the last electron of Zinc which is located in the $4 {s}^{2}$ orbital are:

The Principal Quantum Number $n = 4$

The Angular Momentum Quantum Number $l = 0$

The Magnetic Quantum Number ${m}_{l} = 0$

The Electron Spin Quantum Number ${m}_{s} = + \frac{1}{2} \text{ or} - \frac{1}{2}$