(a) When a 4.75-g sample of solid ammonium nitrate dissolves in 60.0 g of water in a coffee-cup calorimeter (see figure), the temperature drops from 23.0�‹C to 16.6�‹C. Calculate ƒ¢H (in kJ/mol NH4NO3) for the solution process
NH4NO3(s) �¨ NH4+(aq) + NO3−(aq).
Assume that the specific heat of the solution is the same as that of pure water.