Question

An experiment to measure the enthalpy change for the reaction of aqueous copper(II) sulfate, CuSO4(aq) and zinc, Zn(s) was carried out in a coffee cup calorimeter as follows. Cu2+(aq) + Zn(s) → Cu(s) + Zn2+(aq)

50.0 cm3 of 1.00 mol dm–3 copper(II) sulfate solution was placed in a polystyrene cup and its average temperature after three readings was noted to be 25OC and the zinc powder was added . The final temperature was noted to be 91.5 OC. Calulate the heat of the reaction in kJ 

Answer 1

$∆T=91.5−25=66.5°C$

Moles = $1.00×\frac{50.0}{1000}=0.05moles$

$Mass= 159.609×0.05=7.98grams$

$Heat = 4.18 × 7.98 × 66.5 =2,218.2kJ$