Chemical reaction equilibrium

When you are considering the chemical reaction equilibria, the equilibrium constant (K) obviously plays a major role in describing the kinetics of the reaction at the temperature being studied. That is what makes K such a useful parameter, telling a plant designer at an early stage if a chemical product will be formed or not. So how do you calculate K2, well its pretty straight forward:

with K1 the equilibrium constant at 298K and assuming hrxn is not a function of temperature, I'll discuss the method for determining K2 when hrxn(T) in a later post, the reason for using K1 at 298K  is that experimental data is regularly available for chemicals at this temperature:

Enthalpy  chemical  i at 298K

Gibbs energy of chemical i at 298K

Thus using 298K values as your basis, and working from there. K2 and T2 values are the wanted equilibrium constant and the new temperature, respectively. 

with:

          and             

and:

with T1 obviously being 298K, because that is what the experimental data has accounted for.

 From the following graph we can see the temperature dependence of K.

It is always easier to understand something at the hand of an example, lets consider 

At T = 298K the equilibrium constant is K = 4.69 and at T = 333 the equilibrium constant is K = 37.28, with the product yield being directly proportional the size of K.