. The temperature of the
calorimeter increases by 3.2 oC. Calculate the enthalpy
of combustion per mole of quinone. (4 points)CHE 11, Fall 1998
Quiz 6
October 23, 1998
Show your work for full credit. Give your answers with the correct number of significant figures.
1. A sample of quinone (C6H4O2,
0.1964 g) is burned in a calorimeter that has a heat capacity of
. The temperature of the
calorimeter increases by 3.2 oC. Calculate the enthalpy
of combustion per mole of quinone. (4 points)
2. Calculate the DHo for the following reaction, given the heats of formation in the attached table. (3 points)
| 2 NH3 (g) | + | 3 O2 (g) | + | 2 CH4 (g) |  |
2 HCN (g) | + | 6 H2O (g) |
3. Find DH for the following reaction. (4 points)
| C2H2 (g) | + | 2 H2 (g) | |
C2H6 (g) |
| 2 C2H2 (g) | + | 5 O2 (g) | |
4 CO2 (g) | + | 2 H2O (g) | DH = -2599.1 kJ/mol |
| H2 (g) | + |  |
1/2 O2 (g) | |
H2O (g) | DH = -286.0 kJ/mol |
| C2H6 (g) | + | 7/2 O2 (g) | |
2 CO2 (g) | + | 3 H2O (g) | DH = -1559.8 kJ/mol |