Question

The correct statement regarding the third orbit of hydrogen atom is:

• A. It can accommodate maximum of nine electrons
• B. It contains nine degenerate atomic orbitals
• C. It contains nine atomic orbitals having three sets of degeneracy
• D. It contains nine sub-shells

Answer 1

The correct option is B It contains nine degenerate atomic orbitals

The maximum number of electrons that can be accomodated in the third orbit of $H-$ atom is
$2n^2=2\times 9=18$

In $H-atom$, the orbitals (five 3d, three 3p and one 3s) have same energy. So, they are called degenerate orbitals. Thus the third orbit of $H$- atom contains nine degenerate atomic orbitals.

The third orbit of $H-$ atom contains three sub - shells which are 3s, 3p and 3d respectively.