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standard potentials question feasibility

Hey! Please help me.
For the hydrogen peroxide half equation, should I combine the bottom 2? If I do, what will the E value b? (before combining with the manganate half equation)
image-b462dc1f-2042-4e30-bc39-bfc6902bcf5c-2135616697-compressed.jpg.jpeg

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hydrogen peroxide is H2O2.

So to construct an equation, first identify which one will be getting reduced (losing electrons) and which one will be getting oxidised (gaining electrons).

then to find the emf of the cell, just do cell which is reduced - cell which is oxidised.
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Avatar for sarah99630
sarah99630
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Original post by BTAnonymous
hydrogen peroxide is H2O2.

So to construct an equation, first identify which one will be getting reduced (losing electrons) and which one will be getting oxidised (gaining electrons).

then to find the emf of the cell, just do cell which is reduced - cell which is oxidised.


yeah thanks, but they're usually 2 half equations for that...in this case there are 3, 2 of which contain H202 and im not sure how to go about it
Original post by sarah99630
yeah thanks, but they're usually 2 half equations for that...in this case there are 3, 2 of which contain H202 and im not sure how to go about it


Try out the possibilities using E(cell) = E(red) - E(ox)

If the answer is positive then the reaction is feasible (spontaneous)
How is it +0.84?. i thought it's 1.77 - 1.52 ?
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D.SHA64
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Original post by loooooooooool0
How is it +0.84?. i thought it's 1.77 - 1.52 ?


same
Original post by loooooooooool0
How is it +0.84?. i thought it's 1.77 - 1.52 ?


E(cell) = E(red) - E(ox)

The reduced state is the manganate(VII)
The oxidised state is the hydrogen peroxide

E(cell) = 1.52 - 0.68 = +0.84V
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sarah99630
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Original post by charco
Try out the possibilities using E(cell) = E(red) - E(ox)

If the answer is positive then the reaction is feasible (spontaneous)


Thank you loaaads!! Yes only one of them gives a positive answer...so is the E values are the sole reason as to why only one of the peroxide equations would be applicable in this case? (to give a positive E cell)
Original post by sarah99630
Thank you loaaads!! Yes only one of them gives a positive answer...so is the E values are the sole reason as to why only one of the peroxide equations would be applicable in this case? (to give a positive E cell)


yes

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