Explain why a mixture formed will act as a buffer?

Question

Explain why a mixture formed by mixing 100 mL of 0.100 M HC2H3O2 and 50 mL of 0.100 M NaOH will act as a buffer?

Answer 1

HC2H3O2 is a weak acid ; NaOH is a strong base.

The acid and the base will react according to the net equation

HC2H3O2 + OH- >> C2H3O2- + H2O

So we get a buffer solution that consists of a weak acid (HC2H3O2) plus one of its salts(C2H3O2-)