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# Chemistry redox Watch

1. (Original post by CheeseIsVeg)
Yep so, sorry was eating food!
So we have an ion here.
So whatever happens, we need the sum of the oxidation states to have a charge of -2

We've spoken about Oxygen always being -2
So here we have 4 oxygens, each with -2
-2 times 4 = -8

Now hold on

We need an overall charge of -2
The only other species we have here is Mn
so its oxidation number must be ?
+2??
2. (Original post by Lucky10)
+2??
Not quite.
Do you do maths? would it benefit you if I set it out algebraically?
3. (Original post by CheeseIsVeg)
Not quite.
Do you do maths? would it benefit you if I set it out algebraically?
Yeha it would
4. (Original post by Lucky10)
Yeha it would
AWESOME

So the overall charge is -2 right?
And we've 4 oxygens at -2
so -2 times 4 = -8

Let the oxidation state of Mn be x

-8 + x = -2

Now can you work out what the oxidation state of Mn is (x) ?

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Updated: November 13, 2016
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