Question

What is equilibrium and its types?

Answer 1

Part 1: Definition of Equilibrium

1. Equilibrium is defined as the state when the rate of the forward reaction is equal to the rate of backward reaction.
2. This implies that the concentration of reactant is equal to the concentration of the products without any change in the system's properties.
3. Chemical equilibrium is dynamic in nature because reaction continues to occur even after equilibrium is achieved.
4. The rate of reaction can be calculated as the ratio of the concentration of the product over the concentration of reactants.

Part 2: Types of equilibrium

1. There are two types of equilibrium exist namely: Homogenous and Heterogenous equilibrium
2. Homogenous equilibrium is the type of equilibrium where the reactant and products both are found in the same phase.

• Homogenous equilibrium is also divided into two categories: When reactant and product is having an equal number of molecules or when reactant and product is not having an equal number of molecules.
• When reactant and product is having an equal number of molecules for example:
  ${\mathrm{H}}_2\left(\mathrm{g}\right)+{\mathrm{I}}_2\left(\mathrm{g}\right)\rightleftharpoons 2\mathrm{HI}\left(\mathrm{g}\right)$
• When reactant and product is not having an equal number of molecules. for example:
  $2{\mathrm{SO}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\rightleftharpoons 2{\mathrm{SO}}_3\left(\mathrm{g}\right)$

1. Heterogeneous equilibrium: It is the type of equilibrium where the reactant and products both are found in the different phase.
2. For example:
   ${\mathrm{CO}}_2\left(\mathrm{g}\right)+\mathrm{C}\left(\mathrm{s}\right)\rightleftharpoons 2\mathrm{CO}\left(\mathrm{g}\right)$