A sample of copper absorbs 43.6 kJ of heat, resulting in a temperature rise of 75.0°C, determine the mass (in kg) of the copper sample if the specific heat capacity of copper is 0.385 J/g°C.

Question

A sample of copper absorbs 43.6 kJ of heat, resulting in a temperature rise of 75.0°C, determine the mass (in kg) of the copper sample if the specific heat capacity of copper is 0.385 J/g°C.

	A.	1.51 kg
	B.	6.62 kg
	C.	1.26 kg
	D.	7.94 kg

Answer 1

q = mC∆T

q = heat = 43.6 kJ = 43,600 J

m = mass = ?

C = specific heat of copper = 0.385 J/g/deg

∆T = change in temperature =75.0ºC

Rearranging and solving for m (mass) we have m = q/C∆T

m = 43,600 J/(0.385 J/g/deg)(75.0 deg)

m = 1510 g x 1 kg/1000 g = 1.510 kg = 1.51 kg (to 3 significant figures) <-- ANSWER A