When 50.0 mL of 1.60 M of HCl(aq) is combined with 50.0 mL of 1.70 M of NaOH(aq) in a coffee-cup calorimeter, the temperature of the solution increases by 10.7°C. What is the change in enthalpy for this balanced reaction?
HCl(aq) + NaOH(aq) ? NaCl(aq) + H₂O( $\ell$ )
Assume that the solution density is 1.00 g/mL and the specific heat capacity of the solution is 4.18 J/g?°C.

Question

When 50.0 mL of 1.60 M of HCl(aq) is combined with 50.0 mL of 1.70 M of NaOH(aq) in a coffee-cup calorimeter, the temperature of the solution increases by 10.7°C. What is the change in enthalpy for this balanced reaction?
HCl(aq) + NaOH(aq) ? NaCl(aq) + H₂O(

\ell

)
Assume that the solution density is 1.00 g/mL and the specific heat capacity of the solution is 4.18 J/g?°C.

Quizplus · Accepted Answer

The reaction is exothermic, so the change in enthalpy is negative. Calculate the heat absorbed by the solution using q = mcΔT, where m = 100 g (since 100 mL of solution), c = 4.18 J/g°C, and ΔT = 10.7°C. Convert the heat from joules to kilojoules and divide by the moles of limiting reactant (HCl or NaOH) to find ΔH per mole.

When 500 ML of 1 ℓ\ellℓ ) Assume That the Solution Density Is 1

When 500 ML of 1 $\ell$ )
Assume That the Solution Density Is 1