Isothermal Removal or Addition of Heat

This occurs in the case of a bath large enough that the addition or removal of an amount of heat Q does not effect its temperature T, such as a bath consisting of a system undergoing an isothermal phase change. Then from Eq.3.10.1  

To this purpose, we combine Eq.3.10.1 with the definition of heat capacity, Eq. 1.13.1, which yields on a molar basis  

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