I keep getting different answers... It's in group 11 or 1B, so does it only have one? I've heard two, as well. IDK
copper can have many oxidation numbers because it is a transition elements ..
Copper can have a +1 or a +2 charge. However, since the word equation is copper(II) bromide that means you need to use the copper 2+ bromide has a 1- charge in orger to balance the charges you need 2 bromides for each copper that way there is a 2+ and a 2- CuBr2
