Hello,

I am trying to write a chemical equation for a reaction I did and I cannot for the life of me figure out how to do it. I added cobalt chlorid hexahydrate, NH4Cl, NH4OH, H2O2 and HCl. The major product was [Co(NH3)5Cl]Cl2 but I don't know what the other ones would be... I don't know how I would figure it out. Any hints would be really helpful. Thanks

2 answers

The initial CoCl2.6H2O probably is oxidized by the H2O2 to Co^+3 which is what you have in the [Co(NH3)5Cl]Cl2, the other product of H2O2 is H2O. The NH4OH added is easier to handle if you do it as NH3 + H2O (same thing but much easier to see how the NH3 gets into the coordination sphere for Co). The NH4Cl/NH4OH is there as a buffer as well as to furnish the NH3 for the Co coordination. I would leave the NH4Cl as NH4Cl. And the HCl is there to furnish the Cl^- for the extra Cl that must be present for the ionic charge increase from +2 to +3 for Co. I hope these hints are sufficient.
Thanks alot = )