Question

a 0.10kg piece of copper at an initial temperature of 95C is dropped into 0.20kg of water contained in a 0.28kg aluminum calorimeter. the water and calorimeter are initially at 15C. what is the final temperature of the system when it reaches equilibrium?

Answer 1

Use the law of conservation of energy and assuming no heat loss to the surroundings, then

Heat given up by copper = heat absorbed by water + heat absorbed by calorimeter

Working formula is

Q = heat = MCp(delta T)

where

M = mass of the substance

Cp = specific heat of the substance

delta T = change in temperature

Heat given up by copper = 0.10(387)(95 - T)

Heat absorbed by water = 0.20(4186)(T - 15)

Heat absorbed by calorimeter = 0.28(899)(T - 15) \

where

T = final temperature of the system

Substituting appropriate values,

0.10(387)(95 - T) = 0.20(4186)(T - 15) + 0.28(899)(T - 15)

38.7(95 - T) = 1088.92(T - 15)

3676.50 - 38.7T = 1088.92T - 16333.8

1127.62T = 20010.3

T = 17.75 C