Answer
a. $HC{O_3}^-$ is the weaker acid.
b. $H_2O$ is the weaker acid.
c. $H_2CO_3$ is the weaker acid.
Work Step by Step
Table 11.3 contains the relative strengths of these acids.
The acid strength increases from bottom to top. Therefore, if acid A is above acid B in this table, A is stronger than B.