mixtures

• what is a mixture?

  two or more substances that NOT chemically combined.
• what can the substance in a mixture be?

  elements or compounds (or both)
• what does 'no chemical bonds' mean?

  when substance is apart of mixture the properties don't change (stays the same)
• how can substances in mixtures be separated?

  physically
• what do separating mixtures not involve?

  chemical reactions
• what is a pure substance?

  a substance containing one element or compound
• what can filtration be used for?

  separating insoluble solids from liquids
• what do insoluble solids not dissolve in?

  liquids
• what do holes in filter paper allow liquid to do?

  pass through
• how can soluble solids be separated from a solution?

  crystallisation
• during crystallisation what happens to some solutions when they cool?

  crystals form
• how can a liquid be separated from a solution?

  simple distillation
• when the solution is heated in simple distillation will the part of the solution with the highest or lowest evaporate first?


  lowest
• what is fractional distillation used for?

  separating mixture with different liquids
• what is chromatography used for?

  separating a mixture of soluble substances
• if the substance is more or less soluble will it travel up the chromatography paper?


  more
• how many spots do pure substances make on a chromatogram?

  one
• what are chromatograms used for?

  identifying unknown mixtures