To determine the oxidation number of bromine in HBrO4, we can rely on standard rules for assigning oxidation states.
First, we start with the general knowledge that hydrogen (H) typically has an oxidation number of +1, and oxygen (O) usually has an oxidation number of -2.
The molecule HBrO4 consists of one hydrogen atom, one bromine atom, and four oxygen atoms. Here’s how we can break it down:
- The contribution of hydrogen is +1.
- Each of the four oxygen atoms contributes -2, totaling -8.
Let the oxidation number of bromine be represented as x. We can set up the equation based on the total charge of the molecule, which is neutral (0):
1 (from H) + x (from Br) + 4(-2, from O) = 0
This simplifies to:
1 + x – 8 = 0
So:
x – 7 = 0
x = +7
Thus, the oxidation number of bromine in HBrO4 is +7.