Mixtures

• Mixture


  Made from different substances that are not chemically joined
• Compound


  Substance formed by the chemical union of two or more elements
• Mixtures have variable composition - you can vary the amount of each substance
• Compounds have definite composition - you cannot vary the amount of each element
• Mixtures


  • The different substances are not chemically joined together
  • Each substance in the mixture keeps its own properties
  • Each substance is easily separated from the mixture
• Compounds


  • The different elements are chemically joined together
  • The compound has properties which are different from the elements it contains
  • It can only be separated into its elements using chemical reactions
• Iron and sulfur react together when heated to make a compound called iron sulfide
• In a mixture of iron and sulfur


  The iron and sulfur atoms are not joined together
• In iron sulfide


  The iron and sulfur atoms are joined together
• You can separate the iron from a mixture of iron and sulfur using a magnet, but this does not work for iron sulfide