State Pauli's exclusion principles.

Explanation

Pauli's Exclusion principle : No two electrons in the same atom can have all the four quantum numbers same.
Illustration : In ls orbital there are two electrons, the set of quantum number of one electron differ with another in spin quantum number.
`{:(n,1,m,s,"Total electron"),(1,0,0,+1//2,2 " electrons"),("(K shell)","(1s shell)","(s-orbital)",-1//2,):}`