Equilibrium constant

This presentation will give you a general introduction to the equilibrium constant.

1. Equilibrium Constant Syed Nawaz Shah

2. Equilibrium Constant Consider a general reversible reaction (When a reversible reaction occurs mean forward and backward reactions are happening) A and B are reactants . C and D are products . are coefficients of a balanced chemical equation.   ⇋

3. Equilibrium Constant Let’s understand this by a real equation ⇋ Here are reactants . is a product . The coefficient of and is 1, 3 and 2 respectively.  

4. Definition Equilibrium constant is a number which is obtained by multiplying the equilibrium concentrations ( The concentration at the equilibrium point ) of all the products divided by the product (multiplication) of equilibrium concentrations of all the reactants and the concentration of each substance is raised to the power of its coefficients in the balanced chemical equation. Equilibrium equation for the following reaction ⇋ Here Kc is the equilibrium constant.  

5. Explanation Let’s explain the previous expression. ⇋ (1) (This expression is for the equation no.1 )   Reactants Products Equilibrium constant

6. Explanation Let’s write expression for a real equation ⇋ I think now you can write expression of any equation.   Coefficient of   Coefficient of  

7. Points to remember Equilibrium constant for a reaction at a particular temperature always have the same value. Values of Kc are generally reported without units. Equilibrium constant is temperature dependent. If we write the chemical equation in the reverse direction that is given in the slide no.1 ⇋ Now the expression will change . When the expression will change, then the value of equilibrium constant will change.