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    http://tringscience.pbworks.com/f/f3...nt+june+07.pdf

    q3 a (i).


    The mark scheme says that only A is a hydrocarbon... why aren't they all?
    It also says B isn't an ether group, but surely it is because of the oxygen atom on the end?
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    A hydrocarbon only contains hydrogen and carbon so the other two aren't hydrocarbons because they also contain oxygen.
    B is an aldehyde not an ether because it has a HC=O group on the end. An ether must have an oxygen singly bonded to 2 carbons.
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    (Original post by lollage123)
    http://tringscience.pbworks.com/f/f3...nt+june+07.pdf

    q3 a (i).


    The mark scheme says that only A is a hydrocarbon... why aren't they all?
    It also says B isn't an ether group, but surely it is because of the oxygen atom on the end?
    A hydrocarbon is a molecule which contains only atoms of hydrogen and carbon. Molecules B and C contain oxygen atoms as well as hydrogen and carbon atoms, and thus are not hydrocarbons.

    An ether group is R-O-R', like the one in 5-membered ring in molecule C. B is not an ether group, as it is only connected to 1 carbon atom via a C=O bond. This molecule is actually an aldehyde.
 
 
 
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