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2015 june paper help

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    can someone please explain to me how part a) and b) is done, i am bit confused on the whole question.
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    (Original post by djmans)
    can someone please explain to me how part a) and b) is done, i am bit confused on the whole question.
    Are you familiar with skeletal formula?
    At each vertex, there is a carbon atom. And each carbon will be bonded to hydrogen atoms unless otherwise shown.

    For example, here's partly the structural formula of isovaleric acid

    Can you begin to see what kind of chemical compound this is?
    It's a -COOH functional group, so that should really tell you something.

    As for part b) molecular formula is just the actual number of atoms of each element in a compound.

    For instance, the structural formula of Propan-1-ol is CH3CH2CH2OH.
    But the molecular formula is just C3H8O (sometimes we say C3H7OH)
    I'm simply just counting the number of atoms of each element.

    So in this case, you would count the number of atoms for each element here. I see carbon, hydrogen and oxygen.

    Both questions may be easier if you were to draw out all the carbon atoms and hydrogen atoms, i.e. displayed graphical formula
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