... important, forexample, in the storage of gasoline, which is a mixture of manyhydrocarbons. The storage tanks must be vented to the air andconsequently water vapor can condense in the tanks. ... constituents, onthe temperature, and on the pressure. Therefore the change in free energy arising from changes inany of these quantities can be written as the sumIt is to be understood that each of the ... to changes of the amount of anyconstituent, changes of temperature, or changes of pressure — all evaluated, of course, at someparticular concentration, temperature, and pressure. An important...