chemical changes

• What do metals produce when they react with oxygen?

  Metal oxides
• Why are the reactions of metals with oxygen classified as oxidation reactions?

  Because the metals gain oxygen
• What do metal atoms form when they react with other substances?

  Positive ions
• How is the reactivity of a metal related to its tendency to form positive ions?

  The more reactive the metal, the more likely it is to form positive ions
• What is the order of reactivity for the metals potassium, sodium, lithium, calcium, magnesium, zinc, iron, and copper?

  • Potassium
  • Sodium
  • Calcium
  • Magnesium
  • Zinc
  • Iron
  • Copper
• What happens when a more reactive metal is placed with a less reactive metal in a compound?

  The more reactive metal can displace the less reactive metal
• What is the chemical equation for the reaction of calcium with oxygen?

  2 Ca + O2 → 2 CaO
• What is the chemical equation for the reaction of potassium with oxygen?

  4 K + O2 → 2 K2O
• How do reactive metals like magnesium behave in oxygen?

  They burn with a flame
• How do less reactive metals like iron behave in oxygen?

  They tarnish and change color without a flame
• What is the reactivity series of metals from most reactive to least reactive?

  1. Potassium
  2. Sodium
  3. Calcium
  4. Magnesium
  5. Aluminium
  6. Carbon
  7. Zinc
  8. Iron
  9. Tin

  10. Lead

  11. Hydrogen

  12. Copper

  13. Silver

  14. Gold
• Why are hydrogen and carbon included in the reactivity series?

  They are often used as reference points for metal reactivity
• What do reactive metals like potassium, sodium, and calcium produce when they react with cold water?

  Bubbles of hydrogen gas
• What happens when metals above hydrogen in the reactivity series react with acids?

  They produce bubbles of hydrogen gas
• What is the relationship between the reactivity of a metal and the speed of the reaction with acids?

  The more reactive the metal, the faster the reaction
• What happens to metals below hydrogen in the reactivity series when they react with acids?

  They do not react with acids
• What mnemonic can be used to remember the most important metals in the reactivity series?

  Please Stop Calling My Aunty Zebra In The Class
• What is a displacement reaction?

  A reaction where a more reactive metal displaces a less reactive metal from a compound
• What is the equation for the displacement reaction of copper sulfate with magnesium?

  CuSO4 + Mg → Cu + MgSO4
• How are unreactive metals like gold found in the Earth?

  • Found as the metal itself
  • Most metals are found as compounds
  • Require chemical reactions to extract
• How are metals above carbon in the reactivity series typically extracted?

  By electrolysis or displacement reactions
• What is reduction in the context of metal extraction?

  Loss of oxygen
• How is iron oxide reduced in the blast furnace?

  By reacting with carbon or carbon monoxide
• What is the ionic equation for the reduction of iron oxide?

  Fe2O3 + 3CO → 2Fe + 3CO2
• What happens to zinc in a displacement reaction with copper sulfate?

  Zinc loses electrons and is oxidized
• What is the half equation for zinc oxidizing?

  Zn → Zn2+ + 2e-
• What is the half equation for copper reducing?

  Cu2+ + 2e- → Cu
• What is the general reaction of acids with metals?

  • Metal + acid → salt + hydrogen
  • Produces bubbles of hydrogen gas
  • Metals above hydrogen react, below do not
• What is the equation for magnesium reacting with hydrochloric acid?

  Mg + 2HCl → MgCl2 + H2
• What is the equation for zinc reacting with hydrochloric acid?

  Zn + 2HCl → ZnCl2 + H2
• What is the equation for iron reacting with hydrochloric acid?

  Fe + 2HCl → FeCl2 + H2
• What is the equation for magnesium reacting with sulfuric acid?

  Mg + H2SO4 → MgSO4 + H2
• What is the equation for zinc reacting with sulfuric acid?

  Zn + H2SO4 → ZnSO4 + H2
• What is the equation for iron reacting with sulfuric acid?

  Fe + H2SO4 → FeSO4 + H2
• How can the reactions of acids with metals be represented as ionic equations?

  By excluding spectator ions
• What is the ionic equation for magnesium reacting with hydrogen ions?

  Mg + 2H+ → Mg2+ + H2
• What is the ionic equation for iron reacting with hydrogen ions?

  Fe + 2H+ → Fe2+ + H2
• What is the ionic equation for zinc reacting with hydrogen ions?

  Zn + 2H+ → Zn2+ + H2
• What is the ionic equation for the neutralization of an acid by a base?

  H+ + OH- → H2O
• What happens in neutralization reactions between acids and bases?

  • Hydrogen ions react with hydroxide ions
  • Produces water
  • Can be represented by the ionic equation: H+ + OH- → H2O