Define buffer and types of buffer, a.acid buffer, b.basic buffer

 Buffer

• A buffer solution is a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid that resists changes in pH upon addition of small amounts of acid or base.
• It helps to maintain a stable pH in a solution, even when small amounts of strong acid or base are added. 
• There are two main types of buffer solutions: acid buffers and basic buffers.

a. An acid buffer 

• It is a solution is a mixture of a weak acid and its conjugate base.
• It helps to resist changes in pH when small amounts of a base are added to the solution. 
• An example of an acid buffer solution is a mixture of acetic acid (CH3COOH) and sodium acetate (CH3COONa).

b. A basic buffer 

• It is a solution is a mixture of a weak base and its conjugate acid.
• It helps to resist changes in pH when small amounts of an acid are added to the solution. 
• An example of a basic buffer solution is a mixture of ammonia (NH3) and ammonium chloride (NH4Cl).