Question

quantum levels of zincs last level?

Answer 1

In order to explain clearly let's have a look at elements before Zinc

Nickel (Atomic Number = 28)

Electronic configuration of Nickel : 2, 8,16, 2

Sub shell electronic configuration of Nickel : 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d8

In nickel the last subshell is 3d, so we expect the valence electron of next element (Copper) to be filled in 3d which makes 3d9 but 3d9 configuration is highly unstable whereas half-filled and completely filled subshell has got more stability. Hence one of the 4s2 electrons also jumps to this 3d9 making it 3d10 and becomes highly stable and completely filled. So the configuration of next element (Copper) is given as below

Copper (Atomic Number = 29)

Electronic configuration of Copper : 2, 8,18, 1

Sub shell electronic configuration of Copper : 1s2 2s2 2p6 3s2 3p6 4s1 3d10

Since 3d is completely filled now, the next electron will enter into the 4s subshell making it 4s2. So the electronic configuration of the next element (Zinc) is given by,

Zinc (Atomic Number = 30)

Electronic configuration of Zinc : 2, 8,18, 2

Sub shell electronic configuration of Zinc : 1s2 2s2 2p6 3s2 3p6 3d10 4s2

So for zinc, the last electron enters in the 4s subshell making it 4s2

Therefore, the Quantum number of the last electron of Zinc which is located in the 4s2 orbital are:

Principal Quantum Number, n = 4

Angular Momentum Quantum Number, l = 0

Magnetic Quantum Number, ml = 0

Electron Spin Quantum Number, ms = +1/2 or−1/2