Complete the following chemical equations:
(i) ${\mathrm{Ca}}_3{\mathrm{P}}_2+{\mathrm{H}}_2\mathrm{O}\to$
(ii) $\mathrm{Cu}+{\mathrm{H}}_2{\mathrm{SO}}_4$ (conc.) $\to$
OR
Arrange the following in order of property indicated against each set:
(i) $\mathrm{HF},\mathrm{HCl},\mathrm{HBr}$, $\mathrm{HI}$ : increasing bond dissociation enthalpy
(ii) ${\mathrm{H}}_2\mathrm{O},{\mathrm{H}}_2\mathrm{S},{\mathrm{H}}_2\mathrm{Se},{\mathrm{H}}_2\mathrm{Te}$, increasing acidic character.