chemical changes

• What do metals form when they react with oxygen?


  Metal oxides
• What type of reaction is it when metals react with oxygen and gain oxygen?

  Oxidation
• What type of reaction is it when a metal oxide loses oxygen?

  Reduction
• What happens in an oxidation reaction involving oxygen?

  The gain of oxygen
• What happens in a reduction reaction involving oxygen?

  The loss of oxygen
• What do metals form when they react with other substances?

  Metal ions
• What is the reactivity of a metal related to?

  Its tendency to form positive ions
• What is the reactivity series of metals?

  A chart showing metals in order of decreasing reactivity
• Put the metals zinc, potassium, copper, lithium, sodium, calcium, magnesium and iron in decreasing order of reactivity

  Potassium, sodium, lithium, calcium, magnesium, zinc, iron and copper
• What other non-metal elements are often included in the reactivity series?

  Carbon and hydrogen
• What is displacement?


  When a more reactive metal displaces a less reactive metal from a compound
• What is produced when a metal reacts with water?

  A metal hydroxide and hydrogen gas
• Describe the reaction of potassium, sodium and lithium with water and acid

  Violent
• Describe the reaction of calcium with water and acid

  Fast
• Describe the reaction of magnesium with water

  Slow
• Describe the reaction of magnesium and acid

  Rapid
• Describe the reaction of zinc with oxygen

  Slow
• Describe the reaction of zinc with water

  Usually no reaction
• Describe the reaction of zinc with acid

  Slow
• Describe the reaction of copper with water and acid

  No reaction
• What is produced when a metal reacts with an acid?


  A metal salt and hydrogen gas
• What happens in an oxidation reaction in terms of electrons?

  The loss of electrons
• What happens in a reduction reaction in terms of electrons?

  The gain of electrons
• What is the reaction called when oxidation and reduction take place at the same time?

  A redox reaction
• What is an ionic equation?

  A chemical equation that shows how positively charged ions join with negatively charged ions to make a compound
• Write the ionic equation for the displacement reaction between Magnesium and Copper Sulfate solution

  Mg(s) + Cu2+(aq) → Mg2+(aq) + Cu(s)
• Write the half equation for the oxidation of Magnesium

  Mg(s) → Mg2+(aq) + 2e-
• Write the half equation for the reduction of the copper ion Cu2+


  Cu2+(aq) + 2e- → Cu(s)
• How are unreactive metals found in the Earth's crust?

  As the metal itself
• Name two metals found as elements in the Earth's crust

  Gold, platinum
• How are most metals found in the Earth's crust?

  As metal compounds
• How do extract metal from a metal compound?

  By chemical reactions
• How do you extract metals from metal oxides when the metal is less reactive than Carbon?

  By reduction with carbon
• Why can Carbon extract iron from iron oxide?

  Because it more reactive than iron
• What is an ore?

  A rock that contains enough of a metal or a metal compound to make extracting the metal worthwhile
• How do you extract metals from metal oxides when the metal is more reactive than Carbon?


  By electrolysis of the metal compound
• When acids react with some metals what is produced?

  A metal salt and hydrogen
• What is produced when magnesium reacts with hydrochloric acid?

  Magnesium chloride and hydrogen
• What is produced when zinc reacts with sulfuric acid?


  Zinc sulfate and hydrogen
• What type of reaction is it when an acid reacts with an alkali?

  Neutralisation