SC 4.2

• 1. Different metals have different reactivity to oxygen. The more reactive metals react more vigorously with oxygen
  2. In vigorous reaction, between a more reactive metals such as potassium with oxygen, a bright flame is observed
  3. In a less vigorous reaction between less reactive metals such as iron with oxygen, only embers or slow colour changes can be observed
• A reactivity series of metals is formed based on the reactivity of metals with oxygen

  • Potassium K, Sodium Na, Calcium Ca, Magnesium Mg, Aluminium Al, (Carbon), Zinc Zn, (Hydrogen), Iron Fe, Tin Sn, Lead Pb, Copper Cu, Mercury Hg, Silver Ag, Gold Au
  • Kalau NAk KA(Ca)hwin Mesti Ada Zinc Ferum Supaya Perjalanan hidup Cukup HanGus AnGkat AUstralia
• • In the reactivity series of metals, carbon is located between aluminium and zinc while hydrogen is located between zinc and iron
  • Although carbon is a non-metallic element, it is able to remove a less reactive metal, such as zinc from zinc oxide
  • Zinc oxide + carbon --> Zinc + carbon dioxide
• Application of the reactivity series of metals

  • Metals that are more reactive than carbon or are located higher than carbon in the reactivity series of metals (Potassium, Sodium, Calcium , Magnesium, Aluminium) are extracted by electrolysis
  • These metals are extracted by passing an electric current through the molten ores
  • Metal oxide -electric current-> metal + oxygen
• Application of the reactivity series of metals

  • Metals which are less reactive than carbon, which are positioned lower than carbon in the reactivity series of metals (zinc, iron, tin and lead) are extracted by heating the ores with carbon (coke)
  • Metal oxide + Carbon -heat-> metal + carbon dioxide