Chemistry - Complete P-block Question with Solution | TestHub

Three reactions involving ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$are given below : (i) ${\mathrm{H}}_3{\mathrm{PO}}_4+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_3{\mathrm{O}}^{+}+{\mathrm{H}}_2{\mathrm{PO}}_4^{-}$ (ii) ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{HPO}}_4^{2-}+{\mathrm{H}}_3{\mathrm{O}}^{+}$ (iii) ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}+{\mathrm{OH}}^{-}\to {\mathrm{H}}_3{\mathrm{PO}}_4+{\mathrm{O}}^{2-}$ In which of the above does ${\mathrm{H}}_2{\mathrm{PO}}_4^{-}$act as an acid ?