Question

write a note on the working of a basic buffer ​

Answer 1

Answer:

A buffer is a solution containing either a weak acid and its salt or a weak base and its salt, which is resistant to changes in pH. ... For a given buffer solution, there is a working pH range and a set amount of acid or base that can be neutralized before the pH will change.

Answer 2

Answer

It is prepared by mixing a weak base and its salt with a strong acid.

1. NH₄OH + NH₄CI
2. NH₄OH + (NH₄)₂ SO₄

Action of basic buffer solution:

The reserve acidity of basic buffer is due to cation of the solution and the reserve basicity of a basic buffer is due to the weak base of the solution.

Consider the buffer solution NH₄OH + NH₄Cl. In this buffer NH₄OH is a weak electrolyte and ionises only to some extent. NH₄CL is a strong electrolyte and ionises to a greater extent to give NH₄ and Cl¯ ions.

(i) Addition of a few drops of a strong acid: The H+ ions of added acid combine with NH₄OH to form H₂O and NH₄ions. So, pH value does not change.

$\sf NH_4OH + H^+ \to NH^+_4 + H_2O$

(ii) Addition of few drops of a strong base : The OH¯ ions of added base combine with NH₄ ions to form undissociated NH₄OH. So pH value does not change.

$\sf OH^- + NH_4 \to NH_4OH$