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chem question a level

hi, please can i have some help on this question? I've tried writing half equations so 2Fe3+ + H+ + 2e- --> 2Fe2+ +H+ but I'm not sure how the equation for (NH3OH)+ will work?
Here is the question: https://ibb.co/YcGhZcq
Thanks!!
Original post by anonymous56754
hi, please can i have some help on this question? I've tried writing half equations so 2Fe3+ + H+ + 2e- --> 2Fe2+ +H+ but I'm not sure how the equation for (NH3OH)+ will work?
Here is the question: https://ibb.co/YcGhZcq
Thanks!!

They’ve said the reacting ratio of NH3OH^+ to Fe^3+ is 1:2 and as you have correctly identified, each Fe^3+ accepts a single electron to give Fe^2+.

So it stands to reason that each NH3OH^+ loses two electrons (or more precisely, the nitrogen loses the electrons since each H is already in its max oxidation state and O is more electronegative than N, so it’s easier to pull off the electrons from nitrogen).

What is the oxidation state of nitrogen in NH3OH^+ and what will it be after the loss of 2e^-? Which nitrogen-containing species contains nitrogen in the same oxidation state?
Original post by TypicalNerd
They’ve said the reacting ratio of NH3OH^+ to Fe^3+ is 1:2 and as you have correctly identified, each Fe^3+ accepts a single electron to give Fe^2+.
So it stands to reason that each NH3OH^+ loses two electrons (or more precisely, the nitrogen loses the electrons since each H is already in its max oxidation state and O is more electronegative than N, so it’s easier to pull off the electrons from nitrogen).
What is the oxidation state of nitrogen in NH3OH^+ and what will it be after the loss of 2e^-? Which nitrogen-containing species contains nitrogen in the same oxidation state?

Ohhhh I see, nitrogen is -1 so when it loses 2 electrons it becomes +1 which is n2o. Thanks!
Original post by anonymous56754
Ohhhh I see, nitrogen is -1 so when it loses 2 electrons it becomes +1 which is n2o. Thanks!

Yeah, that’s basically it. The alternative was to just take the products that were options and make half equations out of them, but that would have taken forever
Is that q AS1 or AS2
Original post by Jerom Shino
Is that q AS1 or AS2

It could come up on either AS or A2, since AS gives you all the knowledge required to do it.
Original post by Jerom Shino
Is that q AS1 or AS2

This was an AS paper CIE

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