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    (Original post by BrokenS0ulz)
    Thanks! One question though, how come it wouldn't allow just the NH2 in the amide to be protonated? It only allowed the amine To be protonated
    its because amino acids can exist as zwitterions so only affects the -COOH group or amine group of an amino acid. the other amine group was from an amide
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    (Original post by BrokenS0ulz)
    Thanks! One question though, how come it wouldn't allow just the NH2 in the amide to be protonated? It only allowed the amine To be protonated
    If you were to think of a general structure of the amino acid the amide bit is part of the R group.
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    (Original post by nats927)
    its because amino acids can exist as zwitterions so only affects the -COOH group or amine group of an amino acid. the other amine group was from an amide
    (Original post by LordGaben)
    If you were to think of a general structure of the amino acid the amide bit is part of the R group.
    Oh right, thanks!
    But say if it were in high acid concentration, then the NH2 in the amide would also be protonated too?
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    (Original post by BrokenS0ulz)
    Oh right, thanks!
    But say if it were in high acid concentration, then the NH2 in the amide would also be protonated too?
    Yh and I would expect the COO- on the zwitterion to also be protonated. Actually Im starting to doubt an amide can be protonated in a similar way to an amine. They are most likely far weaker bases. This might need some research.
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    What's the mark scheme specific definition for glass transition temperature?
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    (Original post by BrokenS0ulz)
    Oh right, thanks!
    But say if it were in high acid concentration, then the NH2 in the amide would also be protonated too?
    ' It should be noted that while amides are considered to be non-acidic and non-basic underphysiologic conditions, this functional group can be "protonated" (act as a base) or unprotonated(act as an acid) under more extreme chemical conditions. amides may be at least partially protonated and, in the presence of very strong bases, anamide hydrogen may be removed '
    found from an online source.
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    (Original post by LordGaben)
    Yh and I would expect the COO- on the zwitterion to also be protonated. Actually Im starting to doubt an amide can be protonated in a similar way to an amine. They are most likely far weaker bases. This might need some research.
    (Original post by nats927)
    ' It should be noted that while amides are considered to be non-acidic and non-basic underphysiologic conditions, this functional group can be "protonated" (act as a base) or unprotonated(act as an acid) under more extreme chemical conditions. amides may be at least partially protonated and, in the presence of very strong bases, anamide hydrogen may be removed '
    found from an online source.
    I assume for our syllabus the only thing they would expect us to know is that a zwitter ion only has a charge on the NH3+ and COO- that isn't in the R group. Thanks for the help, both of you
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    Hey everyone. I have an A-level chemistry whatsapp group and was wondering if anybody would like to join. We have a thriving community of 60+ individuals and the group will be immensely beneficial for exams. If your interested pm me your contact number. Thanks.
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    is the hydrolysis of proteins the same conditions as hydrolysis of amides? so moderately concentrated NaOH heated under reflux ->carboxylate salts
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    (Original post by nats927)
    is the hydrolysis of proteins the same conditions as hydrolysis of amides? so moderately concentrated NaOH heated under reflux ->carboxylate salts
    Yep moderately concentrated hcl or Naoh, heat under reflux.
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    What reagent/condition needed for ester hydrolysis?
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    (Original post by Hattie0912)
    What reagent/condition needed for ester hydrolysis?
    dilute sulfuric acid heated under reflux
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    (Original post by nats927)
    dilute sulfuric acid heated under reflux
    Nope, it's moderately concentrated, you lose the mark for dilute
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    (Original post by Lh22)
    Nope, it's moderately concentrated, you lose the mark for dilute
    no... they said hydolysis of esters.. not condensation. concentrated sulfuric acid is for the condensation reaction.
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    Does anyone have/ know of any good revision notes? I need an A in chemistry and am really struggling with the A2 papers
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    does anyone have a list of the reactions we need to know for F334???
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    Hey all, had a few questions which I found a bit strange.

    June 2013 Q1cii)
    The structure of A is -ooc(C6H4)coo- which I obtain correctly
    The has formed from the carboxylic acid part of the molecule so should have a C=O bond peak at 1700-1725. However the markscheme says it should be at 1720-1740 (which would be an aldehyde!). But it also says reference to anything other than a carboxylic acid/carboxylate is a CON so it sort of contradicts itself. Any help?

    Jan 2013 Q2a)
    Why doesn't the hydroxyl group act as an acid? because don't OH groups deprotonate?
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    (Original post by Mooresy)
    Does anyone have/ know of any good revision notes? I need an A in chemistry and am really struggling with the A2 papers
    It may or may not be too late in the day but the CGP revision guide for this course helped me out SO much for F335 as the salters one is far too brief and misses out stuff!


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    (Original post by lydiaaa1)
    What's the mark scheme specific definition for glass transition temperature?
    The temperature below which a polymer turns brittle. It's vital to state 'below which'


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    (Original post by Welbeck)
    Hey all, had a few questions which I found a bit strange.

    June 2013 Q1cii)
    The structure of A is -ooc(C6H4)coo- which I obtain correctly
    The has formed from the carboxylic acid part of the molecule so should have a C=O bond peak at 1700-1725. However the markscheme says it should be at 1720-1740 (which would be an aldehyde!). But it also says reference to anything other than a carboxylic acid/carboxylate is a CON so it sort of contradicts itself. Any help?

    Jan 2013 Q2a)
    Why doesn't the hydroxyl group act as an acid? because don't OH groups deprotonate?
    For Jan 2013 Q2a), OH (alone) groups have low delocalisation (Compared to carboxylic acids and phenols)
 
 
 
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