Question

When 5.00 g of barium hydroxide are added to 250.0 mL of 0.250 hydrochloric acid in a calorimeter, the temperature off the solution increases from 25.0 C to 28.0 C. Calculate the enthalpy ( in kJ per mole of water) given the density of the hydrochloric acid is 1.01 g/mL and the resulting solution is sufficiently dilute that its specific heat is 4.184 J/g C

Answer 1

Ba(OH)2 + 2HCl ==> 2H2O + BaCl2
mols Ba(OH)2 = 5/molar mass = about 0.029 but confirm that.
mols HCl = M x L = about 0.06.
Ba(OH)2 is the limiting reagent and 0.029*2 = mols H2O produced.
q = mass H2O x specific heat H2O x (Tfinal-Tinitial) = ?J

Convert J/(2*0.029 mol H2O) to kJ/mol.