For one of the substances in Table 3.2, compute the final pressure when the substance is heated from 15°C and 1 bar to 25°C at constant volume.

Question

Table 3.2 provides the specific volume, isothermal compressibility, and volume expansivity of several liquids at 20°C and 1 bar25, where ? and ? may be assumed constant.

Answer 1

First ethanol will be chosen as the substance to be used. In the problem the volume is held constant, both the temperature and pressure come into play here. We start with the equation



At constant volume, it becomes



Integrating



and solving for P2 gives



Plugging in the values gives



Leading P2 = 126.11 bar