Which compound will absorb the maximum amount of heat when dissolved in the same amount of water ? (Integral heats of solution at` 25^(@)C` in kcal/mol of each solute are given in brackets)

Options

A. `HNO_(3)(Delta H= -33)`
B. `KCl (Delta H= +17.64)`
C. `NH_(4)NO_(3)(Delta H= +25.5)`
D. `HCl (Delta H= -74.1)`

Answer

C

Explanation

`NH_(4)NO_(3)(s) rarr NH_(4)NO_(3) (aq), Delta H_(s)= 25.5`
`NH_(4)NO_(3)(aq) hArr NH_(4)^(+) (aq) + NO_(3)^(-) (aq), Delta H_("diss")`
More +ve is `Delta H_(S)`, more is the heat of dissociation