Answer
$HClO_2$ is the stronger acid.
Work Step by Step
- $HClO_2$ and $HClO$ have the same central atom: $Cl$
Therefore, the difference here will be the number of oxygen connected to the central atom.
$HClO_2$ has 2 oxygen.
$HClO$ has 1 oxygen.
So: $HClO_2$ is more acidic.
