Powdered zinc was reacted with 25.00 cm3 of 1.000 mol dm−3 copper(II) sulfate solution in an insulated beaker. Temperature was plotted against time.
The maximum temperature used to calculate the enthalpy change of reaction was chosen at a point on the extrapolated (red) line.
The formula q=mcΔT was used to calculate the amount of energy released.
The values used in the calculation were m=25.00 g and c=4.18 J g−1 K−1 .