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

BOARD

(a) Account for the following :

(i) The acidic strength decreases in the order$HCl>{H}_{2}S>P{H}_{3}$

(ii) Tendency to form pentahalides decreases down the group in group 15 of the periodic table.

(b) Complete the following chemical equations :

(i) ${P}_{4}+S{O}_{2}C{l}_{2}\to$

(ii) $Xe{F}_{2}+{H}_{2}O\to$

(iii) ${I}_{2}+\underset{\left(conc\right)}{HN{O}_{3}\to }$

(a) (i) Because of decrease in electronegativity from chlorine to phosphorus, the bond dissociation enthalpy from HCl to H-P increases and their tendency to release H+ decreases and thus acidic strength decreases.

(ii) Down the group, the tendency of next 's' orbital's electron to jump to previous 'd' orbital decreases very much due to inert pair effect.

(b) (i)

(ii) $Xe{F}_{2}+2{H}_{2}O\to 2Xe+4HF+{O}_{2}$

(iii)

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