Question

If there are three possible values $(+\frac{1}{2},0,-\frac{1}{2})$ for the spin quantum number, then the maximum number of electrons in second orbit will become:

• A. 8 electrons
• B. 6 electrons
• C. 12 electrons
• D. 27 electrons

Answer 1

The correct option is C 12 electrons

Since three spin quantum numbers are possible for an electron, then the maximum number of electrons that can be accomodated in an orbital is 3.

Total number of orbitals in a shell = $n^2$
Maximum number of electrons in a shell = $3n^2$

Therefore, for $n=2$
Maximum number of electrons that can be accommodated $=3n^2=3\times 2^2=12$ electrons