Chemistry - PERIODIC TABLE Question with Solution | TestHub

Atomic number$\left(15\right)$electronic configuration is
$\left(15\right)\to 1{\mathrm{s}}^2,2{\mathrm{s}}^2,2{\mathrm{p}}^6,3{\mathrm{s}}^2,3{\mathrm{p}}^3$
and this element is Phosphorous.
Group no$=15$
Valence${\mathrm{e}}^{-}\Rightarrow {\mathrm{e}}^{-}$present in valence shell
$=2+3=5$
Valency$=3$, it needs$3$electron to complete its octet.