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Reduction of water (1 Viewer)

samwell

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is the following eqn possible for the reduction of water:
4H2O+electron =4OH- + 4H+ :confused:$@mu-l
 

twilight1412

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i dont think its considered reduction
but then again i havent done this in a while
as far as i know its the ATOMS which are reduced/oxidised and not the molecule as a whole?

anyway
reduction is where the valance changes/becomes more negative
but the valence of H is still +1
and the valence on 0 is still -2
 

samwell

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True dat i dont know wat i waz thinking. this is more of electrolysis dan reduction. i may lose 1 mark 4 it
tnks
 

YannY

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Haha you know what? you guys did a oxidation of water.

2 H2O + H2 -> 2 H3O+

That is the reduction of water.

2H<SUB>2</SUB>O + 4e<SUP>-</SUP> + O<SUB>2</SUB> ---> 4OH<SUP>- </SUP>
is oxidation of water as indicated by the - which shows a gain of electron.
 

independantz

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YannY said:
Haha you know what? you guys did a oxidation of water.

2 H2O + H2 -> 2 H3O+

That is the reduction of water.

2H<SUB>2</SUB>O + 4e<SUP>-</SUP> + O<SUB>2</SUB> ---> 4OH<SUP>- </SUP>
is oxidation of water as indicated by the - which shows a gain of electron.
Umm, Oxidation is loss? 0_0
 

GMK

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The whole oil rig thing-Oxidation is loss of electrons, Reduction is gain of electrons. i.e. oxidation reduces the charge and reduction increases the charge.
 

twilight1412

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^ the first part of your post is correct but the second part is wrong

because electrons have NEGATIVE CHARGE
a gain in electrons lowers the charge
 

Undermyskin

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2H2O + 4e- + O2 ---> 4OH-

LOLZ. This is the reduction of water! It's not wrong! OILRIG. Reductant like alkali metals become oxidized and have + signs. Thus, the reverse is the reduction equation, gaining e-...
 

cameron0110

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The reduction of water is actually 2H2O +2e- => H2 + 2OH- because one hydrogen in each water goes from oxidation state 1+ to 0. In the other equations that have been written, its actually the oxygen that is being reduced.

The first equation (H2O => H+ + OH-) isn't actually a redox equation at all if you check the charge balance, its the self-ionisation of water.

The best way to think about oxidation/reduction is using the oxidation state because if something is oxidised the oxidation state increases and if its reduced the oxidation state is reduced.
 

xiao1985

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cameron0110 said:
The reduction of water is actually 2H2O +2e- => H2 + 2OH- because one hydrogen in each water goes from oxidation state 1+ to 0. In the other equations that have been written, its actually the oxygen that is being reduced.

The first equation (H2O => H+ + OH-) isn't actually a redox equation at all if you check the charge balance, its the self-ionisation of water.

The best way to think about oxidation/reduction is using the oxidation state because if something is oxidised the oxidation state increases and if its reduced the oxidation state is reduced.
oops my bad...

i automatically linked reduction of water with shipwrecks

you are right, reduction of water forms H2 gas.
 

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