When a 0.235-g sample of benzoic acid is combusted in a
bomb calorimeter (Figure 5.19), the temperature rises 1.642 °C.
When a 0.265-g sample of caffeine, C8H10O2N4, is burned, the
temperature rises 1.525 °C. Using the value for the
heat of combustion of benzoic acid, calculate the heat of combustion
per mole of caffeine at constant volume. (b) Assuming
that there is an uncertainty of 0.002 °C in each temperature
reading and that the masses of samples are measured to 0.001
g, what is the estimated uncertainty in the value calculated for
the heat of combustion per mole of caffeine?