ms = -1/2
Up to 4p, the energy levels go as follows:
1s 2s 2p 3s 3p 4s 3d 4p
Ms = + 1/2
ms= +1/2
ms = -1/2
M1 = -1
A 3s electron
Ms = + 1/2
Ms = + 1/2
ms = -1/2
ms= +1/2
ms= +1/2
ml = -1
ml = -1
ms -1/2
ms=-1/2
ms -1/2
L-1 electron configuration
A 3s electron