A 125.0 g block of copper initially at 22.4 °C is heated electrically
PHYSICS · Multi-part · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
A 125.0 g block of copper initially at 22.4 °C is heated electrically. After 95.0 s, the block’s temperature rises to 45.8 °C. During this time, the heater delivered 3.21 × 10^3 J of energy to the copper.
Copper has a molar mass of 63.55 g mol⁻¹.
Assume no heat is lost to the surroundings.
(a) Determine the quantity of heat (in J) absorbed by the copper block during the heating interval.
(b) Using your result from part (a), calculate the value of the heat capacity expressed per mole of copper atoms (in J mol⁻¹ K⁻¹).
(c) Convert the molar heat capacity obtained in part (b) to a value expressed per gram of copper (in J g⁻¹ K⁻¹).
(d) The literature value for the specific heat capacity of copper is 0.385 J g⁻¹ K⁻¹. Compare this value to the result from part (c) and offer one plausible explanation for any discrepancy.