Steven C. answered • 03/13/16
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Mathematics Tutor Steven
Oxidation levels in reactants:
Cu = +2
I = -1
Oxidation levels in productions:
Cu in CuI = +1
I in CuI = -1
I in I2 = 0
Electrons transferred:
2 electrons go from I- to Cu2+
Half reactions (unbalanced):
Cu2+ + e- --> Cu1+
2I- --> I2 + 2e-
Steven C.
Depends on the information you want to convey. It helps to see exactly what the electrons do (so unbalanced) but if you want to do a step-wise balancing of the overall equation, balancing them may be better. Probably balance them to be safe though (just multiply the reduction equation (top one) by 2).
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03/13/16
Meghna R.
okay thanks :) but say it is a thiosulphate titration question, the overall equation for the first stage is:
2Cu2+ + 4I- --> I2 + 2CuI
the equations above wouldn't balance to give this would it? I would have to add an extra 2 iodide ions but I'm not sure where they would go..?
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03/13/16
Rory F.
How do we know that Cu in CuI has a +1 while I in CuI has a -1? In other words how do we know that CU didn't keep its +2 charge causing I in CuI to have a -2 charge?
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04/19/17
Meghna R.
03/13/16