Just one sec...
Hey! Sign in to get help with your study questionsNew here? Join for free to post

Redox Equilibria

Announcements Posted on
Help us uncover the truth about exam cheats – is cheating ever ok? What if you wouldn't get caught? 27-06-2016
    • Thread Starter
    Offline

    ReputationRep:
    Given the following redox reactions:

    Name:  eq_0d8175.gif
Views: 73
Size:  2.6 KB

    How many moles of iron (II) ethandioate FeC2O4 are oxidised by 1 mol of dichromate Cr2O72–(aq)?

    (I thought the answer was 2. However the mark scheme says 3, and does not explain why.)
    Offline

    ReputationRep:
    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
    • Thread Starter
    Offline

    ReputationRep:
    (Original post by HeatherJarvo)
    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
    Thank you. I asked my teacher, he said the mark scheme got it wrong.
    Offline

    ReputationRep:
    (Original post by Gattsu)
    Thank you. I asked my teacher, he said the mark scheme got it wrong.
    that's a scary thought isn't it? It's possible to lose marks on the exam by getting the answer correct.... eek!!
    Offline

    ReputationRep:
    (Original post by Gattsu)
    Given the following redox reactions:

    Name:  eq_0d8175.gif
Views: 73
Size:  2.6 KB

    How many moles of iron (II) ethandioate FeC2O4 are oxidised by 1 mol of dichromate Cr2O72–(aq)?

    (I thought the answer was 2. However the mark scheme says 3, and does not explain why.)

    (Original post by HeatherJarvo)
    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
    Couldnt figure out how you form iron (II) ethandioate FeC2O4 in the first place !?
    Offline

    ReputationRep:
    (Original post by arvin_infinity)
    Couldnt figure out how you form iron (II) ethandioate FeC2O4 in the first place !?
    Why can you not form it?

    Offline

    ReputationRep:
    (Original post by thegodofgod)
    Why can you not form it?

    Oh no..I meant , how you form it according the the equation given to you
    Offline

    ReputationRep:
    (Original post by arvin_infinity)
    Oh no..I meant , how you form it according the the equation given to you
    Fe2+ + (COOH)2 --> [Fe(COO)2] + 2H+
    Offline

    ReputationRep:
    (Original post by charco)
    Fe2+ + (COOH)2 --> [Fe(COO)2] + 2H+
    COOH is not given to us !!!

    I guess I misunderstood the question

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: March 31, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

Poll
Who would make the best Labour leader now?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22

Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.