Chapter 9, Problem 9.50PAE

9.50 When a 13.0-g sample of NaOH(s) dissolves in 400.0 mL of water in a coffee cup calorimeter, the temperature of the water changes from 22.6°C to 30.7C Assuming that the specific heat capacity of the solution is the same as for water, calculate (a) the heat transfer from system to surroundings and (b) $\Delta \text{H}$ for the reaction

   $\text{NaOH(s)}\to {\text{Na}}^{+}\text{(aq)}+{\text{OH}}^{-}\text{(aq)}$