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

    0
    ReputationRep:
    (Original post by davidhoughton)
    whats the date of this exam?
    Right now it's 19th June, but this date could change.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by reneetaylor)
    How do photodegradeable polymers operate?
    Photodegrable polymers are synthetic polymers and are resistant when exposed in sunlight for a pre-longed period of time. They contain a carbonyl group (functional group) within the backbone and they absorb light energy/sun light which results in the polymer being broken down into smaller fragments.
    Offline

    1
    ReputationRep:
    (Original post by otrivine)
    Photodegrable polymers are synthetic polymers and are resistant when exposed in sunlight for a pre-longed period of time. They contain a carbonyl group (functional group) within the backbone and they absorb light energy/sun light which results in the polymer being broken down into smaller fragments.
    Correct, nicely put
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by reneetaylor)
    Correct, nicely put
    thanks !


    Describe what the peaks represent in a carbon-13 spectrum (1)
    Offline

    2
    ReputationRep:
    (Original post by otrivine)
    thanks !


    Describe what the peaks represent in a carbon-13 spectrum (1)
    A carbon environment. No. of peaks = no of different carbon environments.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Natalie21)
    A carbon environment. No. of peaks = no of different carbon environments.
    yes correct.

    my turn
    • Study Helper
    Offline

    3
    ReputationRep:
    I'm back now, can I join in?


    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    (Original post by MasterYi)
    Can someone expalin to me the meaning of mobile phase and stationary phase. I 've seen a couple of vagues definitions and I'm not sure what to use as a go to definition.
    The stationary phase is where molecules from the samples can adsorb to, it can be a solid or a liquid supported on a solid, silica gel is an example of a stationary phase.

    The mobile phase is either a liquid or gas, which brings the samples with it as it travels up the stationary phase.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by MathsNerd1)
    I'm back now, can I join in?


    Posted from TSR Mobile

    wow!! you came

    ask me
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by otrivine)
    wow!! you came

    ask me
    Well I did say I would come back once I'm more confident with the content, so here I am and okay, start off easy then.

    Show the mechanism of halogenation to the benzene ring in diagrams and explain why a halogen carrier is needed. (4)


    Posted from TSR Mobile
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by MathsNerd1)
    Well I did say I would come back once I'm more confident with the content, so here I am and okay, start off easy then.

    Show the mechanism of halogenation to the benzene ring in diagrams and explain why a halogen carrier is needed. (4)


    Posted from TSR Mobile
    do you want me to draw it in paper?

    Halogen carrier is needed because benzene is stable and has a lower pie electron density and therefore there is less polarisation of halogenation and therefore, a halogen carrier is needed.
    Offline

    0
    ReputationRep:
    (Original post by reneetaylor)
    The stationary phase is where molecules from the samples can adsorb to, it can be a solid or a liquid supported on a solid, silica gel is an example of a stationary phase.

    The mobile phase is either a liquid or gas, which brings the samples with it as it travels up the stationary phase.
    Thanks. Can't even give you a thumbs up because I've given too many to you already.
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by otrivine)
    do you want me to draw it in paper?

    Halogen carrier is needed because benzene is stable and has a lower pie electron density and therefore there is less polarisation of halogenation and therefore, a halogen carrier is needed.
    Yeah if you wouldn't mind and that's correct


    Posted from TSR Mobile
    Offline

    1
    ReputationRep:
    (Original post by MasterYi)
    Thanks. Can't even give you a thumbs up because I've given too many to you already.
    Haha, thanks!
    No problem, glad I helped
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by otrivine)
    here, mechanism
    Correct, now my turn


    Posted from TSR Mobile
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by MathsNerd1)
    Correct, now my turn


    Posted from TSR Mobile

    Describe in words the mechanism of Nucleophilic Addition (4)
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by MasterYi)
    Thanks. Can't even give you a thumbs up because I've given too many to you already.
    Hi want to join
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by otrivine)
    Describe in words the mechanism of Nucleophilic Addition (4)
    Okay well it occurs in aldehydes and ketones when they react with sodium borohydride and okay the electron deficient carbon atom in the polar C=O bond is attacked by the OH-. The lone pair of electrons forms a bond with the carbon atom and at the same time the pi bond breaks to produce a negatively charged intermediate. This then donates an electron pair to a hydrogen atom from a water molecule to for a dative covalent bond and a OH- ion.


    Posted from TSR Mobile
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by MathsNerd1)
    Okay well it occurs in aldehydes and ketones when they react with sodium borohydride and okay the electron deficient carbon atom in the polar C=O bond is attacked by the OH-. The lone pair of electrons forms a bond with the carbon atom and at the same time the pi bond breaks to produce a negatively charged intermediate. This then donates an electron pair to a hydrogen atom from a water molecule to for a dative covalent bond and a OH- ion.


    Posted from TSR Mobile
    Perfect!

    my turn
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by otrivine)
    Perfect!

    my turn
    Okay, explain how you'd be able to distinguish between a ketone, aldehyde and carboxylic acid (4)


    Posted from TSR Mobile
 
 
 
Poll
If you won £30,000, which of these would you spend it on?

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.