# NEET Chemistry The p-Block Elements (XII) Questions Solved

BOARD

(a) Draw the molecular structure of following compounds :

(i) $Xe{F}_{6}$                                            (ii) ${H}_{2}{S}_{2}{O}_{8}$

(b) Explain the following observations :

(i) The molecules $N{H}_{3}$ and $N{F}_{3}$ have dipole moments which are of opposite direction.

(ii) All the bonds in $PC{l}_{5}$ molecule are not equivalent.

(iii) Sulphur in vapour state exhibits paramagnetism.

(a) (i) $Xe{F}_{6}$ :

(ii) ${H}_{2}{S}_{2}{O}_{8}$ :

(b) (i) Because F is more electronegative than N in $N{F}_{3}$ whereas N is more electronegative than H in $N{H}_{3}.$

(ii) Because $PC{l}_{5}$ has a trigonal bipyramidal structure in which the three equatorial P-Cl bonds are equivalent while the two axial bonds are longer than equatorial bonds.

(iii) Because sulphur in vapour state has two unpaired electrons in the antibonding ${\pi }^{*}$ orbitals like ${O}_{2}.$

Difficulty Level: