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TSR Wiki > Study Help > Subjects and Revision > Revision Notes > Chemistry > Fractional Distillation

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Contents 1 Crude Oil 2 Fractional Distillation 2.1 Properties of fractions at the top 2.2 Properties of fractions at the bottom 3 Comments

Crude Oil

Crude oil is made from dead animals under the sea which were compressed between layers of impermeable rock in sedimentary rock.

Fractional Distillation

Fractional distillation takes place at an oil refinery. The process separates the many hydrocarbons in crude oil into useful mixtures. Hydrocarbons that are separated include refinery gas which is used for gas cookers, and kerosine used for aircraft fuel

Properties of fractions at the top

• Low boiling point
• Burn with a clear flame
• Light coloured
• More runny
• Burn readily
• Are smaller molecules

Properties of fractions at the bottom

• Have a high melting point
• Are darker in colour
• Are thicker
• Less likely to burn
• Are larger molecules
• These hydrocarbons have a high boiling point and have longer carbon chains.

Comments