Chemistry - Complete P-block Question with Solution | TestHub

The reaction $X\stackrel{-{\mathrm{H}}_2\mathrm{O}}{\to }{\mathrm{HPO}}_3$ indicates X is ${\mathrm{H}}_3{\mathrm{PO}}_4$.

For ${\mathrm{H}}_3{\mathrm{PO}}_4$ (X), the basicity is 3.

For $({\mathrm{HPO}}_3{)}_3$ (Y, cyclic trimetaphosphoric acid), the basicity is 3.

The oxidation state of P in both X and Y is +5.

Y, being cyclic trimetaphosphoric acid, contains three P-O-P linkages.

Therefore, options B and D are correct.