I can do it, but it may not be right. The atoms/ions and charges are all balanced, but I'm just not sure.
12Br2 + 12H20 ==> 4BrO3^- +20Br- + 24H+ You can divide this by 4
3Br2 + 3H20 ==> BrO3^- + 5Br^- + 6H+
Element/ion Left Right
Br 3*2 = 6 1 + 5 = 6
H 6 6H+
O 3 3
Charges 0 -1 - 5 + 6 = 0
The H+ represents an Acid. The problem is it says that the reaction takes place in an acid. It is so long ago, I don't remember if this includes being on the right.
