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    (Original post by asdfghjkl12)
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    Which part(s) do you need help with?
    What have you got so far?

    We can't just do your work for you, but we can help you get to the right answers :fluffy:
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    i) should be fairly straightforward

    ii) D because secondary alcohols oxidise to ketone.

    iii) solubility depends on the polarity of the solute and the solvent. Remember that 'like dissolves in like': polar molecules are soluble in polar solvents, and non-polar molecules are soluble in non-polar solvents. Water is polar, but hydrocarbons are non-polar, but they all have some solubility in water. This is because the shorter the chain is, i.e. the less non-polar units in the molecules, the more soluble the hydrocarbon will be. Ethanol has less carbons than the molecules in the question, so it is more soluble.

    iv) D are chiral because they both have a carbon that is bonded to 4 different groups.
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    (Original post by Es0phagus)
    i) should be fairly straightforward

    ii) C because secondary alcohols oxidise to ketone.

    iii) solubility depends on the polarity of the solute and the solvent. Remember that 'like dissolves in like': polar molecules are soluble in polar solvents, and non-polar molecules are soluble in non-polar solvents. Water is polar, but hydrocarbons are non-polar, but they all have some solubility in water. This is because the shorter the chain is, i.e. the less non-polar units in the molecules, the more soluble the hydrocarbon will be. Ethanol has less carbons than the molecules in the question, so it is more soluble.

    iv) A and D are chiral because they both have a carbon that is bonded to 4 different groups.
    Is the chiral carbon in A the one in the middle of the chain? I really can't see why it's chiral because I thought it was attached to two -CH3 groups?


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    (Original post by Saywhatyoumean)
    Is the chiral carbon in A the one in the middle of the chain? I really can't see why it's chiral because I thought it was attached to two -CH3 groups?


    Posted from TSR Mobile
    You're right. I thought it was bonded to an ethane, but it's two methanes.
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    Also, ****, I meant D for question ii. C is a primary alcohol, D is secondary.
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    (Original post by Es0phagus)
    i) should be fairly straightforward

    ii) C because secondary alcohols oxidise to ketone.

    iii) solubility depends on the polarity of the solute and the solvent. Remember that 'like dissolves in like': polar molecules are soluble in polar solvents, and non-polar molecules are soluble in non-polar solvents. Water is polar, but hydrocarbons are non-polar, but they all have some solubility in water. This is because the shorter the chain is, i.e. the less non-polar units in the molecules, the more soluble the hydrocarbon will be. Ethanol has less carbons than the molecules in the question, so it is more soluble.

    iv) A and D are chiral because they both have a carbon that is bonded to 4 different groups.
    For ii it's D.

    It can't be C because the alcohol will oxidise into an aldehyde first since the alcohol group is attached to the end carbon.
    It would be D as the alcohol group is on the second carbon.

    Edit: didn't see your response above.
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    (Original post by Es0phagus)
    You're right. I thought it was bonded to an ethane, but it's two methanes.
    ahh okay, but then what is part IV asking for? Is it asking about enantiomers maybe?


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    (Original post by Saywhatyoumean)
    ahh okay, but then what is part IV asking for? Is it asking about enantiomers maybe?


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    I think because D is chiral it will rotate optical light. The others 3 (A-C) won't rotate.
 
 
 
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