Pure substances and mixtures

• What are the different methods to separate mixtures mentioned in the study material?

  Filtration, crystallisation, simple distillation, fractional distillation, and chromatography
• What is the definition of a pure substance in chemistry?

  • Consists only of one element or one compound
  • Does not contain any other substances
• How is the term 'pure' used differently in chemistry compared to everyday language?

  In chemistry, 'pure' means consisting of only one element or compound, not mixed with others
• What is a mixture in chemistry?

  A mixture consists of two or more substances that are not chemically joined together
• What happens to the chemical properties of substances in a mixture?

  The chemical properties of the substances in a mixture remain unchanged
• What are the characteristics of mixtures in chemistry?

  • Consist of two or more different substances
  • Not chemically joined together
  • Can include elements and compounds
  • Physical processes can separate them
• How can mixtures be separated?

  Mixtures can be separated by physical processes that do not involve chemical reactions
• What is the significance of the phrase "no new substances are made" in the context of separating mixtures?

  It indicates that the separation processes do not involve chemical reactions
• What are the differences between elements, compounds, and mixtures?

  • Elements: Made of one type of atom only
  • Compounds: Formed by the chemical union of two or more elements
  • Mixtures: Two or more substances not chemically joined together