大象传媒

Chemical analysis - (CCEA) Separating mixtures

Most elements are rarely found in their pure form. They are found chemically combined with other elements in compounds. Compounds are often found mixed with other compounds. Mixtures may be separated and analysed.

Part of Combined ScienceStructures, trends, chemical reactions, quantitative chemistry and analysis

Separating mixtures

The substances in a mixture are relatively easy to separate, because they are not chemically joined to each other.

A mixed pile of sweets is separated into four piles of different colours - red, green, yellow and purple.
Figure caption,
The components of a mixture can be separated without chemical reactions

We will look at five different ways of separating mixtures:

The following terms are useful to know when thinking about separating mixtures.

  • a solute is the substance that dissolves in a solvent.
  • a solvent is the liquid in which a solute dissolves.
  • a solution is a solute dissolved in a solvent.
  • a soluble substance is one which will dissolve in a solvent.
  • an insoluble substance is one which does not dissolve in a solvent.
  • a filtrate is a filtered solution.
  • a residue is a solid left behind after filtration.
  • a distillate is a liquid produced by distillation.
  • miscible liquids are ones that can mix together.
  • immiscible liquids cannot be mixed together.
  • evaporation is when a liquid is heated and changes state into a gas.
  • condensation is when a gas cools and changes state into a liquid.