1.1.2 Mixtures

• What is a mixture?

  A combination of two or more substances that are not chemically bonded.
• Are the chemical properties of substances in a mixture changed or unchanged?

  Unchanged.
• List 5 ways of separating mixtures:

  Filtration, crystallisation, simple distillation, fractional distillation and chromatography.
• What is filtration and how does it work to separate a mixture?

  Filtration is a process of separating solids from liquids or gases by passing them through a porous material. It works by allowing the liquid or gas to pass through the pores while trapping the solid particles.
• What is crystallisation and how does it work to separate a mixture?

  Crystallisation is the process of forming solid crystals from a solution or melt. It works by selectively separating the desired solute from the mixture based on differences in solubility.
• What is simple distillation and how does it work to separate a mixture?

  Simple distillation is a method used to separate a mixture of liquids with different boiling points. It works by heating the mixture, causing the liquid with the lower boiling point to vaporize and then condense back into a separate container.
• What is fractional distillation and how does it work to separate a mixture?

  Fractional distillation is a process used to separate a mixture of liquids with different boiling points. It works by heating the mixture and collecting the vapor that is produced at different temperatures.
• What is chromatography and how does it work to separate a mixture?

  Chromatography is a technique used to separate and analyze mixtures. It works by separating the components of a mixture based on their different affinities for a stationary phase and a mobile phase.
• When should filtration be used to separate a mixture?

  When the mixture contains solid particles that are larger than the pores of the filter.
• When should crystallisation be used to separate a mixture?

  When the components of the mixture have different solubilities in a solvent and one component can be selectively crystallised out.
• When should simple distillation be used to separate a mixture?

  When the components of the mixture have significantly different boiling points.
• When should fractional distillation be used to separate a mixture?

  When the components of the mixture have different boiling points.
• When should chromatography be used to separate a mixture?

  When the components of the mixture have different affinities for the stationary and mobile phases.
• What is air a mixture of?

  Gases.
• What is crude oil a mixture of?

  Hydrocarbon molecules.