How to work oxidation numbers with brackets in the equation Watch

Hazel99
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V in (V(H2O)6)2+

Show workings out how you did the oxidation number , because I don't know how too.
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KaylaB
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(Original post by Hazel99)
V in (V(H2O)6)2+

Show workings out how you did the oxidation number , because I don't know how too.
Please say how you started it off then I can help show you the answer so you actually learn from this
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Kvothe the Arcane
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(Original post by Hazel99)
V in (V(H2O)6)2+

Show workings out how you did the oxidation number , because I don't know how too.
Approach it like a simple algebraic equation. You know that water is a molecule, not an ion and that the charge is = -2.
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Hazel99
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(Original post by KaylaB)
Please say how you started it off then I can help show you the answer so you actually learn from this

(H2O)6
^^12+ and 6-
Because the charge is 2+ , V=4- (-6+2). ????
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KaylaB
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(Original post by Hazel99)
(H2O)6
^^12+ and 6-
Because the charge is 2+ , V=4- (-6+2). ????
If we know that the oxidation number for H is 1+, and that O is 2-
We can use this to find the overall charge for H2O 2(1+) + (2-) = 0
So as we know, H2O is neutral and has an overall charge of 0.

We can see that V(H2O)62+ is charged and thus has an overall charge of 2+
So to find the oxidation no. of V, we can use what we know about H2O being neutral to help us
This means that six lots of H2O surround one V atom and leave a 2+ charge

So for the oxidation numbers V + 6(H2O) = 2+
If we know that H2O is 0, that leaves this:
V + 6(0) = 2+
Thus V = 2+
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Pigster
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Quite a number of mistakes in this thread.

Either, do the sum for all atoms: V + 12x+1 + 6x-2 = +2, V = +2

OR summarise as KaylaB correctly did, recognising that water = 2x+1 + 1x-2 = 0, therefore V + 6x0 = +2
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shengoc
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(Original post by Hazel99)
V in (V(H2O)6)2+

Show workings out how you did the oxidation number , because I don't know how too.
As has been mentioned, my favourite includes identifying "no charge" molecule as it is, hence oxidation state of "no charge" molecule would be zero net.

Such example includes H2O, NH3.

In other cases like if you have (OH)3..it would mean hydroxide which is an ion with single negative charge per ion, so three of it would mean -3 net contribution.

It is easier to see this "big picture" sometimes. and nothing helps more than seeing more examples and trying your new found "method".

I have purposely avoided using the term "neutral" molecule to avoid confusing with the idea of pH when i am talking about charge here.
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