Pressure Dependence of Chemical Potential and Drive

Pressure Coefficient As previously stated, the value of the chemical potential of a substance depends not only upon temperature but upon pressure as well. Moreover, the potential generally increases when the pressure increases (Fig. 5.7). 

In a small range of pressures, all the curves can be approximated as linear, comparable to the way in which we described the influence of temperature  

Po is the starting value of the chemical potential for the initial pressure Pq. The pressure coefficient is almost always positive. 

Analogously, the pressure dependence of the chemical drive of a transformation 

Experiment 5.3 Boiling of lukewarm water at low pressure A suction flask is filled to one-third with lukewarm water, closed, and subsequently evacuated with a water aspirator. The water begins to boil. 

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