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    I need a lot of help with these questions. I will be so grateful

    How would you write the formulae for the methyl esters formed from:

    propanoic acid
    methanoic acid
    oxalic acid
    benzanoic acid
    benzyl ethanoic acid (benzene ring with CH2COOH attached - assuming I named it correctly)
    phenyl-3-methanoic acid (phenol with COOH attached - assuming I named it corerctly)

    The bond length for C=O in propanone is 0.122nm and that for C-O in ethanol is 0.143nm. The bond length for the C=O in ethanoic acid appears to be the same as that of the C-O bond and intermediate in length between the C=O and C-O values. Explain these data.

    Write the formulae for each of the following and state what the products of hydrolysis are:

    ethyl ethanoate - would it be ethanoic acid + ethanol?
    methyl ethanoate - would it be methanoic acid + methanol?
    ethyl methanoate - methanoic acid + ethanol?
    ethyl benzonate - benzanoic acid + ethanol?
    propanoyl chloride -?

    1. Carboxylic acids are neutralised by concentrated ammonia solution. The salt, when heated, forms an amide. Write the two-step equation for the formation of propanamide.
    2. An alternative method is to form the acid chloride and react this with concentrated ammonia solution. Write this two-step equation.
    3. Suggest why the acid chloride route gives a better yield for amide.
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    (Original post by muffin_selight)
    I need a lot of help with these questions. I will be so grateful

    How would you write the formulae for the methyl esters formed from:

    propanoic acid
    methanoic acid
    oxalic acid
    benzanoic acid
    benzyl ethanoic acid (benzene ring with CH2COOH attached - assuming I named it correctly)
    phenyl-3-methanoic acid (phenol with COOH attached - assuming I named it corerctly)
    Drawing out the structural formulae will help. You know that an ester is formed from a carboxylic acid and an alcohol with loss of water. See if you can identify where the water would be lost from then you can see what ester bonds to form.


    (Original post by muffin_selight)

    The bond length for C=O in propanone is 0.122nm and that for C-O in ethanol is 0.143nm. The bond length for the C=O in ethanoic acid appears to be the same as that of the C-O bond and intermediate in length between the C=O and C-O values. Explain these data.
    What do you know about the relationship between bond strength and length?


    (Original post by muffin_selight)

    Write the formulae for each of the following and state what the products of hydrolysis are:

    ethyl ethanoate - would it be ethanoic acid + ethanol?
    methyl ethanoate - would it be methanoic acid + methanol?
    ethyl methanoate - methanoic acid + ethanol?
    ethyl benzonate - benzanoic acid + ethanol?
    propanoyl chloride -?
    Hydrolysis is the reverse of the reaction I mentioned above; you use water to split the ester into its original constituent species. In the answers you have given I think you have become a confused with which part of the name refers to either of the acid part or the alcohol part, but you seem to have the right idea.

    Propanoyl chloride is similar in structure to an ester; and will react analogously. You will end up with a carboxylic acid and a small Cl based acid molecule...


    (Original post by muffin_selight)

    1. Carboxylic acids are neutralised by concentrated ammonia solution. The salt, when heated, forms an amide. Write the two-step equation for the formation of propanamide.
    2. An alternative method is to form the acid chloride and react this with concentrated ammonia solution. Write this two-step equation.
    3. Suggest why the acid chloride route gives a better yield for amide.
    1. If you want to make propanamide, you'd start with propanoic acid, or the salt of...

    These are pretty simple, you're just writing out the reactants and products
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    Okay, so with regards to the first question, does the H2O come from the -OH in the carboxylic acid and the H from the -OH in the alcohol, or vice versa; does it even matter?

    These are the answers I got for the first question:

    a) methyl propanoate
    b) methyl methanoate
    c) oxyl methanoate??? How would you draw this out?
    d) methyl benzanoate or is it benzoate?
    e) methyl benzylethanoate
    f) methyl phenyl-3-methanoate? How would you draw this out?

    Thanks

    Also, why can't you work out the rate equation from the balanced chemical equation?
 
 
 
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