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AQA GCSE Chemistry Trilogy: Hydrocarbons and Alkanes

Crude Oil:

  • Hydrocarbons are compounds that contain hydrogen and carbon atoms only.

  • Crude oil is a finite resource that is found in the Earth’s crust.

  • It is the remains of organisms that lived and died millions of years ago - mainly plankton, which was buried in mud.

  • Crude oil is a complex mixture of hydrocarbons.

  • Used as -

    • Fuels such as petrol, diesel, kerosene, heavy fuel oil and liquefied petroleum gases

    • Feedstock for the petrochemical industry

    • Solvents

    • Lubricants

    • Detergents

  • A feedstock is a raw material used to provide reactants for an industrial reaction.

  • A petrochemical is a substance made from crude oil using chemical reactions.

Alkanes:

  • Form a homologous series - A 'family' of organic compounds that have the same functional group and similar chemical properties. Alkanes:

    • have the same general formula

    • differ by CH2 in molecular formulae from neighbouring compounds

    • show a gradual variation in physical properties, such as their boiling points

    • have similar chemical properties

  • The general formula for the alkanes is CnH(2n+2), where n is the number of carbon atoms in the molecule.

  • Alkanes are saturated hydrocarbons:

    • Hydrocarbons, because they are compounds containing hydrogen and carbon only

    • Saturated, because their carbon atoms are joined by C-C single bonds

    Alkane Molecules

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AQA GCSE Chemistry Trilogy: Hydrocarbons and Alkanes

Crude Oil:

  • Hydrocarbons are compounds that contain hydrogen and carbon atoms only.

  • Crude oil is a finite resource that is found in the Earth’s crust.

  • It is the remains of organisms that lived and died millions of years ago - mainly plankton, which was buried in mud.

  • Crude oil is a complex mixture of hydrocarbons.

  • Used as -

    • Fuels such as petrol, diesel, kerosene, heavy fuel oil and liquefied petroleum gases

    • Feedstock for the petrochemical industry

    • Solvents

    • Lubricants

    • Detergents

  • A feedstock is a raw material used to provide reactants for an industrial reaction.

  • A petrochemical is a substance made from crude oil using chemical reactions.

Alkanes:

  • Form a homologous series - A 'family' of organic compounds that have the same functional group and similar chemical properties. Alkanes:

    • have the same general formula

    • differ by CH2 in molecular formulae from neighbouring compounds

    • show a gradual variation in physical properties, such as their boiling points

    • have similar chemical properties

  • The general formula for the alkanes is CnH(2n+2), where n is the number of carbon atoms in the molecule.

  • Alkanes are saturated hydrocarbons:

    • Hydrocarbons, because they are compounds containing hydrogen and carbon only

    • Saturated, because their carbon atoms are joined by C-C single bonds

    Alkane Molecules