posted by cassie on .
What is the reduction half-reaction for the following unbalanced redox equation?
Cr2O7^2– + NH4^+ Cr2O3 + N2
B.Cr2O7^2– --> Cr2O3
C.NH4^+ --> N2
D.N2 --> NH4^+
I think this is D...?
in D, nitrogen atoms lose electrons, that is oxidation, right?
So D is not reduction.
A is a reduction
bob for some reason these questions are throwing me off - I need to understand this
In a, the Cr in the dichromate ion is 6
in the chromate ion, the Cr is 3, so each Cr must lose three electrons in that reaction. It is an oxidation of the Cr ion.
Look at B CAREFULLY> you need to think these out. Smart girls don't guess.
Cassie: figure the oxidation state in each ion, on each side, then figure out what change occured: losing or gaining electrons.
I know and I don't want to guess - I want to know it...automatically
thank you for your help