Crude oil is a fossil fuel formed over millions of years from dead plankton. It is a mixture of different hydrocarbons and impurities.

Hydrocarbons are covalent compounds containing hydrogen and carbon atoms only.

Viscosity is how easily a liquid flows. The higher the viscosity, the less easily a liquid flows.

Fractional distillation is a method used to separate miscible fluids (liquids or gases) with different boiling points into individual components (fractions).

A fraction is a part of a mixture that has been separated by fractional distillation.

Fractional distillation of crude oil

Combined science

In the Atmosphere and Changing Climate unit, pupils will build on their understanding of Earth's resources to learn about the evidence for the composition and evolution of the Earth's atmosphere and the impact of human activity on climate change.

In the Earth's Resources unit, pupils learned about the composition and structure of the Earth, and the rock cycle.

Using Earth's resources

a mixture of different hydrocarbons and impurities

What is the name of the method used to separate miscible fluids (liquids or gases) with different boiling points into individual components?

to heat crude oil until it all vapourises

to store the distilled components after separation

What is the purpose of the fractionating column in fractional distillation?

In fractional distillation of crude oil, which of the following fractions has the lowest boiling point?

Components with higher boiling points condense at the top of the column.

Components with lower boiling points condense at the bottom of the column.

Components with lower boiling points condense at the top of the column.

Components with higher boiling points are collected as gases.

Which of the following statement about the separation of components in fractional distillation is true?

They have higher boiling points, are less flammable and more viscous.

They have lower boiling points, are more flammable and less viscous.

They have higher boiling points, are more flammable, and more viscous.

They have lower boiling points, are less flammable, and more viscous.

Which statement about smaller hydrocarbon molecules is true?

Which elements are hydrocarbons composed of?

it is produced quickly by natural processes

it can be replaced within a human lifetime

it forms over millions of years from ancient organic matter

Why is crude oil considered a non-renewable resource?

What key term is used to describe the temperature at which a substance changes from a liquid state to a gas state?

Dead plankton settled at the bottom of the oceans.

The dead plankton was covered in mud and other sediments.

The buried organic matter is subjected to high temperatures and pressures.

Continued heat and pressure breaks downs the organic matter into crude oil.

Order these statements to explain how crude oil is formed.

Why is complete combustion preferred over incomplete combustion?

the ease with which a substance will ignite

a separation technique that uses boiling and condensation

a part of a mixture that has been separated by fractional distillation

Match the definition with the correct key term.

This lesson will be removed by end of Summer Term 2025.

Fractional distillation of crude oil

Lesson outcome

This lesson will be removed by end of Summer Term 2025.