Question:
The group number, number of valence electrons, and valency of an element with atomic number 15 , respectively, are
Correct Option: , 3
Solution:
Atomic number $(\mathrm{Z})=15 \Rightarrow \mathrm{P} \rightarrow[\mathrm{Ne}] 3 \mathrm{~s}^{2} 3 \mathrm{p}^{3}$
Phosphorus belongs to $15^{\text {th }}$ group
number of valence electrons $=5$
and valency $=3$ in ground state.