The Influence of a Change in Heat Capacity

The enthalpy of any substance increases as the temperature increases at constant pressure via Eq. 4.12. The slope of a graph of enthalpy as a function of temperature is the heat capacity of the substance [Cp(A°, where A designates the substance and the means standard state]. The heat capacity is the amount of energy that a substance absorbs as a function of temperature. It relates to all the different ways the substance can store internal energy at constant pressure. For example, vibrational and rotational modes can absorb thermal energy, and a compound that has more such modes will be expected to have a larger heat capacity. 

To get AH n° for the conversion of A to B, we write an equation analogous to Eq. 4.13 for B, and then substraction gives Eq. 4.14. ACp° is the difference in heat capacities between B and A. Since 298ACp° is a constant, we can incorporate it into leading to a new term 

Binding of a molecule A-B to a host H that has completely independent binding regions for the separate entities A and B. 

There is an interesting practical use of Eq. 4.22 that needs to be mentioned. It is common practice to multiply the K, values for binding A and B to the host as a means of estimating the expected binding constant of A-B if no positive or negative cooperativity occurs. Any differ- 

Another form of cooperativity is called multivalency. Multivalency arises when multiple receptors tethered together (often on a surface, such as a biological cell) bind multiple ligands (a term used analogous to guests) that are tethered together. These are very often all 

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