Question

Three atoms of elements with $Z=15,Z=16,Z=17$ are considered. Write their electronic _ configurations and account for the extraordinary stability of one arrangement.

Answer 1

(A) Z=$15$ ${1s}^2{2s}^2{2p}^6{3s}^{2}3p^3$

Z=$16$ ${1s}^2{2s}^2{2p}^6{3s}^{2}3p^4$

Z=$17$ ${1s}^2{2s}^2{2p}^6{3s}^{2}3p^5$

(B) Z=$15$ is unexpectedly stable due to half filled $2p$ orbital which have maximum spin multiplicity which makes it more stable.