Question

Define a buffered solution. What makes up a buffered solution? Explain how buffers absorb added H+ or OH with little pH change. A certain buffer is made by dissolving NaHCO₃ and Na₂CO₃ in some water. Write equations to show how this buffer neutralizes added H+ and OH.

Short answer

An aqueous solution that blocks the changes in pH even adds a small amount of base or an acid called Buffer solution.

Step-by-step solution

Given Information

The buffer consists of NaHCO₃ and Na₂CO₃ in some water.

Buffer solution and its preparation

An aqueous solution that blocks the changes in pH even adds a small amount of base or an acid called Buffer solution.

The preparation of buffer solution using a weak acid pair with its conjugate base or acid. There is a neutralization of acid in a buffered solution of OH-ions when the strong base is added. When the strong acid is added then the base can neutralize the ions of H₃O⁺.

Reaction of carbonate and bicarbonate ions

Take the buffer solution which dissolves NaHCO₃ and Na₂CO₃ in some water. The reaction of carbonate and bicarbonate when the strong acid is added.

$\begin{array}{l}{{\mathrm{CO}}_3}^{2-}+{\mathrm{H}}^{+}\rightleftharpoons {{\mathrm{HCO}}_3}^{-}\\ {{\mathrm{HCO}}_3}^{-}+{\mathrm{OH}}^{-}\rightleftharpoons {{\mathrm{CO}}_3}^{2-}+{\mathrm{H}}_2\mathrm{O}\end{array}$