In aqueous HBrO, the oxidation number of bromine is +1.

Here's the explanation:

In HBrO, bromine is bonded to oxygen and hydrogen. Oxygen typically has an oxidation number of -2, and hydrogen typically has an oxidation number of +1. Let "x" represent the oxidation number of bromine.

To determine the oxidation number of bromine, we can set up the equation:

-2 + x + 1 = 0

Solving for "x", we get:

x = +1

Therefore, the oxidation number of bromine in aqueous HBrO is +1.