Why is a shorter-chain hydrocarbon generally more useful as a fuel than a long-chain one?

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Question

Why is a shorter-chain hydrocarbon generally more useful as a fuel than a long-chain one?

Accepted Answer

It is more volatile and ignites more easily — Award 1 mark. Shorter chains have weaker forces between molecules, so they are runnier, evaporate more readily and burn more cleanly. This is why the petrol fraction is in far greater demand than heavy oils.

Answer

It is more volatile and ignites more easily

Answer

It is less flammable and therefore safer

Answer

It contains more carbon per molecule

Answer

It has a higher boiling point so it stores more easily

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