A calorimeter contains 19.0 mL of water at 12.5, ^{circ}C. When 2.50 g of rm X (a substance with a molar mass of 59.0 g/mol) is added, it dissolves via the reactionrm X{(s)}+H_2O{(l)} rightarrow X{(aq)}and the temperature of the solution increases to 28.5, ^{circ}C.Calculate the enthalpy change, Delta H, for this reaction per mole of rm X.Assume that the specific heat and density of the resulting solution are equal to those of water [4.18 rm J/(g cdot {^circ C}) and 1.00 rm g/mL] and that no heat is lost to the calorimeter itself, nor to the surroundings.