Metals & Acids

• oxidised


  oxygen chemically bonded with an element
• oxidation reaction


  oxygen chemically bonded to another element

  (e.g. carbon + oxygen --> carbon dioxide)
• General Equation (Oxygen):

  Metal + Oxygen --> Metal Oxide
• Diatomic Molecule


  molecules of two atoms bonded together
• aqueous


  diluted/dissolved in water
• The number of atoms of each element in reactants and in the products must be the same.
• Signs of a chemical reaction occuring:

  • bubbles/fizzing (gas released)
  • colour change
  • temperature change
  • smell change
• General Reaction (Acids):

  Metal + Acid --> Salt + Hydrogen
• Positive Test Result:

  • lit (burning) wooden lint makes a squeaky 'pop' sound when placed in a test tube with hydrogen gas (trapped)
• Alkali metals changes colour when reacting with oxygen and moisture in the air.
• The alkali metals react with water to form a metal hydroxide (makes solution alkaline) and hydrogen gas.
• Universal indicator turns blue/purple in alkaline solutions.
• Hydrogen gas tested using a lit splint, squeaky 'pop' sound being made.
• General Equation (Water):

  alkali metal + water --> metal hydroxide + hydrogen
• General Equation (steam):

  metal + water (steam) --> metal oxide + hydrogen
• displacement reaction


  when a more reactive metal displaces a less reactive metal from its compound
• ore


  rock containing metal worth extracting
• Carbon is often used to extract metals from metal ores because it is:

  • more reactive compared to other metals
  • cheap
  • readily available