Question

A common laboratory reaction is the neutralization of an acid with a base. When 50.0 mL of the .500 M HCl at 25 C is assed to 50 mL of .500 M NaOH at 25 C in a coffee cup calorimeter, the temperature of the mixture rises to 28.2 C. What is the heat of reaction per mole of acid? Assume the mixture has a specific heat capacity of 4.18 J/gK and that the densities of the reactant solutions are both 1.00 g/mL

Answer 1

q = heat released = [mass H2O x secific heat H2O x (Tfinal-Tinitial)]

mols of rxn = 0.5M x 0.050 L = 0.025 mols.
q/0.025 = delta H in J/mol. Usually this is quoted in kJ/mol so divide by 1000 for kJ/mol.

Answer 2

912

Answer 3

670J

Answer 4

1339J