outlined, the amount of heat needed to perform each of them must be calculated using the
following equation:
5 . B
This problem uses Hess’s law, which states that heats of reaction may be added to determine
the enthalpy of another reaction. To calculate the heat of formation for one mole of carbon
monoxide, the reaction equations must be manipulated as follows:
The second equation must be reversed:
If the two equations are added together, a third equation is obtained:
This is the formation reaction of carbon monoxide. As in question 3, however, we need to
divide the enthalpy change by two to obtain the value for 1 mole.
6 . D
A negative free energy change signifies that the reaction is spontaneous and that work can be
done. If the energy that is released is coupled to less favorable reactions, they can be driven to
completion. This, for example, is how your body uses the breakdown of ATP to accomplish
certain reactions that normally wouldn’t occur.
7 . B