A 28.5 g piece of gold is heated and then allowed to cool. What is the change in temperature (°C) if the gold releases 0.106 kJ of heat as it cools? The molar heat capacity of gold is 25.4 J/mol･°C.

Question

A 28.5 g piece of gold is heated and then allowed to cool. What is the change in temperature (°C) if the gold releases 0.106 kJ of heat as it cools? The molar heat capacity of gold is 25.4 J/mol･°C.

Answer 1

q = mC∆T

q = heat = 0.106 kJ = 106 J (to get units in joules)

m = mass = 28.5 g

C = specific heat = 25.4 J/molº x 1 mol Au/ 197 g Au = 0.129 J/gº (to get units in grams)

∆T = change in temperature = ?

Solving for ∆T we have,..

∆T = q / mC = 106 J / (28.5 g)(0.129 J/gº)

∆T = 28.8ºC