Self Test Chapter 9C.1B

[LavieTran2B]

Hello,
For this problem, the solutions manual tells us that the answer is pentaamminebromidocobalt(II) sulfate when naming [CoBr(NH3)5]+SO4, however, I'm confused as to why it is not pentaamminebromidocobalt(III) sulfate because the (III) charge on the cobalt and -1 charge on the bromine would cancel out with the -2 charge that SO4 has.

[Wesley Zhou 1F]

Yes, I believe that the book is wrong in this case.

I strongly believe the answer puts Co with a +3 oxidation state, making the pentaamminebromidocobalt compound +2, which cancels out with sulfate's -2 charge.

[Anisa Subbiah 14B 1L]

I also got the same answers, so I think the book is mistaken