change in enthalpy

Question

A calorimeter was used to measure the heat change when an ionic compound dissolves in water. The final mass of the contents of the calorimeter was 51.13 g and the change in temperature was 3.01 °C.

Calculate the heat change of the calorimeter, given that its heat capacity is 7.93 J/°C.

Answer 1

For this problem we can use q = mC∆T

q = heat = ?

m = mass = 51.13 g

C = specific heat capacity = 7.93 J/gº

∆T = change in temperature = 3.01º

q = (51.13 g)(7.93 J/gº)(3.01º)

q = -1220 J (negative sign indicating heat released from reaction to surroundings = exothermic)