TheLearnDen

Year 8 · Science

Separating Mixtures

Year 8 learners practise chromatography filtration and distillation.

The activities include Explain Fractional Distillation, Explore Chromatography, Identify Different Separation Techniques, and related practice. The checked support below includes lesson, video, worksheet, teaching. Open a resource in its provider's website and choose the format that best helps the learner explain the idea independently.

Understand the key idea

A mixture can be separated by choosing a method that uses a difference in physical properties. Filtration uses particle size, evaporation and distillation use boiling point, and chromatography uses differences in solubility and attraction.

Common mix-up

Filtration cannot remove a substance that is dissolved in a liquid because the dissolved particles pass through the filter.

Try this first

  1. Identify every substance in the mixture.
  2. Find a physical property that differs between them.
  3. Choose the method and explain what is collected at each stage.

Ask: Why would filtration work for sand and water but not for salt solution?

Activities covered

  • Explain Fractional Distillation
  • Explore Chromatography
  • Identify Different Separation Techniques
  • Investigate Chromatography
  • Investigate Filtration and Evaporation
  • Investigate Fractional Distillation
  • Learn About Crystallisation

Checked learning resources

  • Pure and impure substances - KS3 Chemistry

    BBC Bitesize · Lesson · Opens on the provider website

    Year 8 Science resource matched to chromatography filtration and distillation.

  • Oak: Distillation Practical

    Oak National Academy · Video · Opens on the provider website

    Year 7 science lesson. I can compare two types of distillation and successfully use distillation to separate a mixture of miscible liquids. Simple distillation is used to separate a mixture containing only two substances

  • Oak: Chromatography

    Oak National Academy · Video · Opens on the provider website

    Year 7 science lesson. I can describe how chromatography works and use a chromatogram to answer questions about a substance. Chromatography can be used for both separation of minute samples and analysis. A pure substance

  • Oak: Separating Pure Salt From Dirty Rock Salt

    Oak National Academy · Video · Opens on the provider website

    Year 7 science lesson. I can suggest how to combine separation techniques in order to separate pure salt from a sample of rock salt. The properties of the substances in a mixture help to determine the technique best suit

  • Oak: Separating A Soluble Solid From A Liquid

    Oak National Academy · Video · Opens on the provider website

    Year 7 science lesson. I can explain how dissolving can be reversed to separate a soluble solid from a liquid. Evaporation can remove solvent from a solution, leading to the production of a saturated solution. Crystallis

  • Oak worksheet: Distillation Practical

    Oak National Academy · Worksheet · Opens on the provider website

    Year 7 science lesson. I can compare two types of distillation and successfully use distillation to separate a mixture of miscible liquids. Simple distillation is used to separate a mixture containing only two substances

  • Oak lesson slides: Distillation Practical

    Oak National Academy · Teaching · Opens on the provider website

    Year 7 science lesson. I can compare two types of distillation and successfully use distillation to separate a mixture of miscible liquids. Simple distillation is used to separate a mixture containing only two substances

  • Oak worksheet: Chromatography

    Oak National Academy · Worksheet · Opens on the provider website

    Year 7 science lesson. I can describe how chromatography works and use a chromatogram to answer questions about a substance. Chromatography can be used for both separation of minute samples and analysis. A pure substance