Hey there! Sign in to join this conversationNew here? Join for free
x Turn on thread page Beta

2016 IGCSE Chemistry Paper 2 Unofficial Mark Scheme 2016 watch

  • View Poll Results: How did Paper 2 IGCSE Chemistry go?
    95-100%
    23
    19.66%
    90-95%
    29
    24.79%
    80-89%
    27
    23.08%
    70-79%
    21
    17.95%
    60-69%
    9
    7.69%
    50-59%
    2
    1.71%
    40-49%
    2
    1.71%
    30-39%
    0
    0%
    20-29%
    2
    1.71%
    <20%
    2
    1.71%

    • Thread Starter
    Offline

    4
    ReputationRep:
    (Original post by pendos)
    Defo 180


    Posted from TSR Mobile
    yes, but do you remember the previous parts of the question? or what question number it was?
    Offline

    0
    ReputationRep:
    (Original post by Lelanor)
    I got 180g. 20 F of electricity = 3 moles of electrons. 3 moles of electrons: 1 mole of aluminium (from half equation given). 20/3 moles of aluminium made. Mass = moles × Mr = 20/3 x 27 = 180 g
    Ikrr!! I did the same exact thing I wonder how people got 540 lol
    • Thread Starter
    Offline

    4
    ReputationRep:
    (Original post by pendos)
    Common misconception, it turns acidic


    Posted from TSR Mobile
    i think both could be right, when neutralised it will be orange (pH 7), but if it turns slightly acidic, it will be red
    Offline

    1
    ReputationRep:
    (Original post by Nurne)
    C8H18 +8 1/2O2 -> 8CO + 9H20


    Posted from TSR Mobile
    nope you're wrong once again. It produces carbon monoxide AND carbon AND water AND carbon dioxide
    Offline

    2
    ReputationRep:
    (Original post by pendos)
    Common misconception, it turns acidic


    Posted from TSR Mobile
    Search definition no excess H+ or OH- ions present. Meaning neutral.


    Posted from TSR Mobile
    Offline

    12
    ReputationRep:
    (Original post by Ashnii34)
    Ikrr!! I did the same exact thing I wonder how people got 540 lol
    They probably didn't realise there were fewer moles of aluminium than electrons and just did 20 x 27 = 540. I think someone I was talking to after the exam said she didn't know how to do it so guessed the method and got that.
    Offline

    1
    ReputationRep:
    (Original post by Nurne)
    Search definition no excess H+ or OH- ions present. Meaning neutral.


    Posted from TSR Mobile
    i have no idea what you are going on about. You are talking down to people like they have no idea. They will accept red because it does turn slightly acidic FACT
    Offline

    2
    ReputationRep:
    (Original post by Niclewis)
    nope you're wrong once again. It produces carbon monoxide AND carbon AND water AND carbon dioxide
    Nope.


    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    there's not much point in arguing because you are just wrong. 100%. You think u know every answer. You don't. You're wrong.
    Offline

    2
    ReputationRep:
    (Original post by Niclewis)
    i have no idea what you are going on about. You are talking down to people like they have no idea. They will accept red because it does turn slightly acidic FACT
    http://www.avogadro.co.uk/chemeqm/ac...n/phcurves.htm


    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    (Original post by Nurne)
    Fe3+ Orange/Brown precipitate
    Fe2+ Dark green precipitate


    Posted from TSR Mobile
    they refuse orange. It's brown.
    Offline

    17
    ReputationRep:
    for the incomplete combustion equation did you have to make all of those products or could it just have been carbon monoxide and water??
    Offline

    2
    ReputationRep:
    (Original post by Niclewis)
    there's not much point in arguing because you are just wrong. 100%. You think u know every answer. You don't. You're wrong.
    No, you are.


    Posted from TSR Mobile
    • Thread Starter
    Offline

    4
    ReputationRep:
    (Original post by defenestrated)
    for the incomplete combustion equation did you have to make all of those products or could it just have been carbon monoxide and water??
    im pretty sure incomplete combustion always produces carbon and co2
    Offline

    1
    ReputationRep:
    u seem to have a problem listening to people. They will accept an acidic colour because it turns slightly acidic following neutralisation because it is close to impossible to completely neutralise it 100%
    • Thread Starter
    Offline

    4
    ReputationRep:
    (Original post by Niclewis)
    they refuse orange. It's brown.
    they have accepted orange/brown in mark schemes
    Offline

    2
    ReputationRep:
    Both will be accepted.
    • Thread Starter
    Offline

    4
    ReputationRep:
    (Original post by Niclewis)
    u seem to have a problem listening to people. They will accept an acidic colour because it turns slightly acidic following neutralisation because it is close to impossible to completely neutralise it 100%
    they should accept accept both colours, both reasons are logical
    Offline

    12
    ReputationRep:
    (Original post by Niclewis)
    there's not much point in arguing because you are just wrong. 100%. You think u know every answer. You don't. You're wrong.
    (Original post by defenestrated)
    for the incomplete combustion equation did you have to make all of those products or could it just have been carbon monoxide and water??
    (Original post by rcmack)
    im pretty sure incomplete combustion always produces carbon and co2
    Cgp has an example with just CO and CO2 (and water)
    Name:  20160615_164236.jpg
Views: 221
Size:  405.8 KB
    Offline

    2
    ReputationRep:
    (Original post by Niclewis)
    nope you're wrong once again. It produces carbon monoxide AND carbon AND water AND carbon dioxide
    Carbon monoxide and water are the only products of incomplete combustion.
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: June 19, 2016
Poll
Do you like carrot cake?

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

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