Elements, Compounds, Mixtures

• define element?


  all of the atoms are the same
• define compounds


  compounds contain 2 or more different elements chemically combined in fixed proportions
• if we want to separate a compound back into its elements we have to use a chemical reaction
• define mixtures


  different elements or compounds that are not chemically combined
• to separate a mixture do you use chemical reactions or physical separation techniques?

  physical separation techniques
• define molecule


  has any elements chemically combined even if they're the same element (Cl2, H20)
• an example of compounds

  CH4 H20 NH3 because there's 2 different molecules
• an example of elements

  CL2 O2 because they contain 2 of the same atoms chemically combined