Answer
$H_2CO_3$ and $NaHCO_3$ can form a buffer solution.
Work Step by Step
1. For a buffer solution, we need:
- 1 Weak acid: $H_2CO_3$
- 1 Weak base: $H{CO_3}^-$.
2. They can't react with each other.
- Since they are a conjugate acid-base pair, that reaction will not happen.
Therefore, this pair can make a buffer solution.
