Worksheet – Thermochemistry 1
Name ____________________________
1.
A piece of stainless steel weighing 1.55 g absorbs 141 J of heat energy when its
temperature increases by 178oC. What is the specific heat of stainless steel?
2.
The specific heat of olive oil is 2.0 J/goC. When 435 J of heat is added to the olive
oil in a pan the temperature increases from 25oC to 110oC. What amount (mass) of
olive oil was placed into the saucepan?
3.
How many kilojoules (kJ) of heat are absorbed when 0.46 g of chloromethane
(C4H5Cl, boiling point 12.3oC) vaporizes at its boiling point? Chloromethane, ∆Hvap =
26.4 kJ/mol.
4.
How many joules of energy are needed to raise the temperature 49.32 g of copper metal
from 23.0oC to 137.0oC?
5.
Calculate the change in enthalpy (H) for these reactions.
a. CH4(g)
+ 2 O2(g)

CO2(g) +

b. CaCO3(s)
c. 2 NO(g)
+
CaO(s)
O2(g)

+
2 NO2(g)
CO2(g)
2 H2O(l)
6.
State whether each reaction in problem 5 is exothermic or endothermic.
7.
Sketch a potential energy graph illustrating the reaction in 5a.
8.
Sketch a potential energy graph illustrating the reaction in 5b.