A calorimeter contains 27.0 mL of water at 11.0 C. When 2.10 g of X (a substance with a molar mass of 74.0 g/mol) is added, it dissolves via the reaction X{(s)}+H_2O{(l)}  ->  X{(aq)} and the temperature of the solution increases to 30.0C. Calculate the enthalpy change, Delta H, for this reaction per mole of X. Assume that the specific heat and density of the resulting solution are equal to those of water [4.18 J/(g .C}) and 1.00  g/mL] and that no heat is lost to the calorimeter itself, nor to the surroundings