A calorimeter contains 21.0 mL of water at 15.0 °C. When 2.10 g of X(a substance with a molar mass of 44.0 g/mol ) is added, it dissolves via the reactionX(s)+H2O(l)→X(aq) and the temperature of the solution increases to 30.0 °C. Calculate the enthalpy change, ΔH, for this reaction per mole of X. 

Assume that the specific heat of the resulting solution is equal to that of water [4.18 J/(g⋅°C)], that density of water is 1.00 g/mL, and that no heat is lost to the calorimeter itself,nor to the surroundings. 

Express the change in enthalpy in kilojoules per mole to three significant figures.