Thursday, 16 May 2013

5.13 understand that fractional distillation of crude oil produces more long-chain hydrocarbons than can be used directly and fewer short-chain hydrocarbons than required and explain why this makes cracking necessary

Long chain hydrocarbons are less flammable and more viscous.
Short chain hydrocarbons burn well and flow well.

Long chain hydrocarbons can be cracked which breaks them up into short chain ones.

4 comments:

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  2. you are a living legend my friend. thank you :)))))))))))

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  3. When it says 'explain why this makes cracking necessary', it's because short-chain hydrocarbons are more useful in industry. For example, few gasoline fractions are produced when crude oil is separated, and since gasoline is needed as fuel for cars, the long-chain hydrocarbons are cracked to produce shorter ones eg. gasoline/petrol...

    I think that's correct...?

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