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• Compound


  A pure substance made up of two or more elements chemically combined, and which cannot be separated by physical means
• Ionic compounds


  Contain metal and non-metal elements joined together as particles called ions
• Naming ionic compounds


  The metal element's symbol is always written first, the non-metal element always takes on the name ending '-ide' unless oxygen is also present
• Examples of ionic compound names

  • PbS is lead sulfide
  • MgCl2 is magnesium chloride
• Naming ionic compounds with oxygen

  The name ending is usually '-ate'
• Examples of ionic compound names with oxygen

  • CuSO4 is copper sulphate
  • KClO3 is potassium chlorate
  • Na2CO3 is sodium carbonate
• Naming ionic compounds with nitrogen

  NaNO3 is sodium nitrate, NaNO2 is sodium nitrite. The ending '-ite' will always have less oxygen than '-ate'
• Covalent compounds


  Contain only non-metals, they are named using prefixes (mono, di, tri, tetra, penta) to show how many of each element is present in the formula
• Examples of covalent compound names

  • CO2 is carbon dioxide
  • NO is nitrogen monoxide
  • SiCl4 is silicon tetrachloride
• Common names for some covalent compounds

  • H2SO4 is sulfuric acid
  • NH3 is ammonia
  • CH4 is methane
  • HCl is hydrochloric acid (or hydrogen chloride if it is a gas)
  • C6H12O6 is glucose
  • C2H5OH is ethanol
  • HNO3 is nitric acid