Practice problems:
1. Calculate the heat gained by 125.0 g of water when it is put into a calorimeter and its temperature is
increased by 90.0°C. The specific heat of water is 4.18 J/g °C. (ans. 47.0 kJ)
2.
1.65 g of napthalene (C10H8) is burned in a calorimeter (assume energy absorbed by the calorimeter
is negligible) containing 2000.0 g of water. The temperature of the water rose from 20.20oC to
25.85oC. Calculate the heat of combustion of of naphthalene (moth balls) in KJ/g. (ans. 28.6
kJ/g)
3. A piece of copper metal (c= 0.385 J/ g oC) with a mass of 6.22 kg at 20.5oC absorbs 727.5 KJ of
heat energy. What is the final temperature of the copper? (ans. = 325 oC)
4. The molar heat of combustion of compound C is 6.5 kJ/g. If I were to burn 15 g of this compound in a
bomb calorimeter with a reservoir that holds 2.50 L of water at 25oC., what would the final
temperature of the water be? (ans. 34.3 oC)
Challenger! The specific heat capacity of silver is 0.240 J/goC. Assuming no heat lost to the container or
environment
calculate the final temperature when 100.0 g of silver at 40.0oC is immersed in 60.0 g of water at 10oC.
(ans. 13 oC