Reactivity series

• Reactions involving metals:

  • Reaction of metal with cold water: Metal + water → metal hydroxide + hydrogen
  • Reaction of metal with steam: Metal + steam → metal oxide + hydrogen
  • Reaction of metal with HCl (acid): Metal + acid → salt + hydrogen
  • Reaction of metal oxide with carbon: Metal oxide + carbon → metal + carbon dioxide
  • Reaction of metal oxide with hydrogen: Metal oxide + hydrogen → metal + steam
  • Thermal decomposition of metal carbonate: Metal carbonate → metal oxide / metal + carbon dioxide
• Reactions of Potassium (K)

  • Reacts very violently with water; hydrogen catches fire
  • Reacts explosively with steam
  • reacts explosively with HCl
  • metal oxide does not react with carbon
  • metal oxide does not react with hydrogen
  • Does not decompose as it is thermally stable
• Reactions of sodium (Na)

  • Reacts violently with water; hydrogen catches fire
  • Reacts explosively with steam
  • Reacts explosively with HCl
  • metal oxide does not react with carbon
  • metal oxide does not react with hydrogen
  • Does not decompose as it is thermally stable
• Reactions of calcium (Ca)

  • reacts readily with water
  • reacts explosively with steam
  • reacts violently with HCl
  • metal oxide does not react with carbon
  • metal oxide does not react with hydrogen
  • decomposes into CaO and CO2
• Reactions of Magnesium (Mg)

  • reacts very slowly with water
  • reacts violently with steam when hot; bright white glow produced
  • reacts rapidly with HCl
  • metal oxide does not react with carbon
  • metal oxide does not react with hydrogen
  • decomposes into MgO and CO2
• Reactions of Zinc (Zn)

  • No reaction with water
  • reacts readily with steam; solid that is yellow when hot and white when cold
  • metal oxide reacts with carbon
  • metal oxide does not react with hydrogen
  • decomposes into ZnO and CO2
• Reactions of Iron (Fe)

  • No reaction with water
  • Reacts slowly with steam; when it is red-hot, so must be constantly heated
  • metal oxide reacts with carbon
  • metal oxide reacts with hydrogen
  • decomposes into Fe2O3 and CO2
• Reactions of Lead (Pb)

  • no reaction with water
  • no reaction with steam
  • No observable reaction with HCl due to protective layer of insoluble PbCl2 formed
  • metal oxide reacts with carbon
  • metal oxide reacts with hydrogen
  • decomposes into PbO and CO2
• Reactions of copper (Cu)

  • no reaction with water
  • no reaction with steam
  • no reaction with HCl
  • metal oxide reacts with carbon
  • metal oxide reacts with hydrogen
  • decomposes into CuO and CO2
• Reactions of silver (Ag)

  • no reaction with water
  • no reaction with steam
  • no reaction with HCl
  • metal oxide reacts with Carbon
  • metal oxide reacts with hydrogen
  • decomposes into silver and CO2
• General reactivity trends

  • For reactions with water, steam and HCl, reactions decrease in explosivity down the reactivity series
  • for metal oxide + carbon, reactions are present only for metals AFTER Zn on the reactivity series
  • for metal oxide + hydrogen, reactions are present only for metals AFTER Fe on the reactivity series
  • decomposition of metal carbonate, metals like potassium and sodium are unaffected as they are very thermally stable
• We must pass H2 over Cu when it is hot until it cools down in the air, because hot Cu metal will react with oxygen to give CuO if hydrogen isn't passed through.
• To gauge reactivity, you can either see temperature change (varies more if metal is more reactive) or effervescence (more effervescence if metal is more reactive)