Join TSR now and get all your revision questions answeredSign up now
    Offline

    1
    ReputationRep:
    (Original post by thers)
    It's hardly surprising to see the grade boundary for an A increase dramatically over time due to the fact that students are practicing each past paper and learning mark schemes. Let's hope tomorrow that we don't​ get a paper that requires basic recall with incredibly high boundaries. (I would have preferred this on f325 though)
    Students are getting better and learning off previous years' mistakes.

    I agree that we shouldn't get a high recall paper, grade boundaries will be high. But January was heavily recall based so I think we'll get an application paper like last June.

    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    can someone explain to me how adsorption/solubility affects rf value/retention time
    as in why does a greater solubility lead to a shorter retention (in my book it says more soluble means they are slowed down more)
    Offline

    0
    ReputationRep:
    I have a feeling transesterification will come up tomorrow.
    Offline

    1
    ReputationRep:
    (Original post by Sly1)
    I have a feeling transesterification will come up tomorrow.
    I have the same prediction as well - I think they will get us to write an equation this time and then go onto some green chemistry on it.
    Offline

    0
    ReputationRep:
    (Original post by printergirl)
    can someone explain to me how adsorption/solubility affects rf value/retention time
    as in why does a greater solubility lead to a shorter retention (in my book it says more soluble means they are slowed down more)
    I thought the more soluble something is the more it's slowed down meaning it has a longer retention time
    Offline

    0
    ReputationRep:
    Ask me a question. Let's revise.


    Posted from TSR Mobile
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by D4rth)
    I just realised. The question tells you the answer of the structure, so you just need to form an equation by balancing.

    Posted from TSR Mobile
    thanks and question e) the last one

    I got

    H2NCH(CH2)2(CH3)OH ? is this acceptable
    Offline

    1
    ReputationRep:
    (Original post by thers)
    I have the same prediction as well - I think they will get us to write an equation this time and then go onto some green chemistry on it.
    what do you think the NMR question will be like?
    Offline

    0
    ReputationRep:
    For two groups to have just the one chemical environment in an NMR spec, do they have to be bonded to the same chemical environment?
    Offline

    1
    ReputationRep:
    What is meant by the term biofuel [1]
    Suggest why there is an increase in the use of biofuels as opposed to fuels obtained from crude oil. [2]
    Offline

    0
    ReputationRep:
    (Original post by thers)
    What is meant by the term biofuel [1]
    Suggest why there is an increase in the use of biofuels as opposed to fuels obtained from crude oil. [2]
    Biofuel is a fuel obtained from natural resources such as plant oil.

    Increases oil prices and environmental awareness.


    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    (Original post by Aikta_S)
    what do you think the NMR question will be like?
    I'm predicting a long C-13 NMR at the end, similar to Jan 11 and maybe a small proton NMR question earlier in the paper. Or maybe they might not ask proton NMR this year.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by thers)
    What is meant by the term biofuel [1]
    Suggest why there is an increase in the use of biofuels as opposed to fuels obtained from crude oil. [2]
    Biofuel= is the process in which fuel is made in an environmentally friendly , does not use co2 , burning of coal so is carbon neutral, the fuel comes from crops, by reaction of triglycerides and alochol

    2) because less co2 released and hence, less impact on global warming

    carbon neutral
    Offline

    0
    ReputationRep:
    C6H5NH2 + H2SO4 >>>>>>>>>>>? ( I got C6H5NH4^+SO4^2-)
    Offline

    1
    ReputationRep:
    Correct 3/3 both


    How many carbon atoms in this molecule? [1]
    Name functional groups present. [1]
    How many chiral centres in this molecule? [1]
    Offline

    0
    ReputationRep:
    HELP!!!!!!!!!!!!!
    i've only got one day to revise for F324 i wasn't able to revise for it before because all my exams were together and i literally had no time!! i have not done any revision at all and im panicking like mad i really need an A* in chemistry and i resat f325 and didn't think i did well so i really need to get the max marks in this paper :? :confused:
    Offline

    0
    ReputationRep:
    (Original post by thers)
    Correct 3/3 both


    How many carbon atoms in this molecule? [1]
    Name functional groups present. [1]
    How many chiral centres in this molecule? [1]
    Can you help me how to work out the number of chiral centres please in structures like this? Thanks
    Offline

    1
    ReputationRep:
    (Original post by thers)
    Correct 3/3 both


    How many carbon atoms in this molecule? [1]
    Name functional groups present. [1]
    How many chiral centres in this molecule? [1]
    19 Carbons (phones are too small)
    4 functional groups - ester, alcohol, alkene, ketone
    1 chiral centre

    Posted from TSR Mobile
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by thers)
    Correct 3/3 both


    How many carbon atoms in this molecule? [1]
    Name functional groups present. [1]
    How many chiral centres in this molecule? [1]
    18 carbon

    alkene, alcochol ,ester ,ketone

    1 chiral
    Offline

    2
    ReputationRep:
    In Jan 13 paper, question 3e(iii), why is it that the NH2 is a singlet and not a doublet? Are you supposed to look at the COOH which has 1H so 1+1 =2 which is a doubleT? :s or have i got this so horribly wrong and you're meant to look at the C its next to (but even then that C has a H?)
    OMG please help, thank you so much
 
 
 
Poll
Which Fantasy Franchise is the best?

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.