# Chemistry

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A calorimeter contains 22.0 mL of water at 14.0 C. When 2.50 g of X (a substance with a molar mass of 66.0 g/mol) is added, it dissolves via the reaction X(s)+H_2O(l)--------> X(aq) and the temperature of the solution increases to 25.5 C. 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.

• Chemistry -

q = mass H2O x specific heat H2O x (Tfinal-Tinitial)

dH = delta H.
dH/g = q/g = q/2.50
dH/mol = q/mol = (q/2.50)*molar mass

• Chemistry -

1755.6 kj/g

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