reactivity of metals

• What do metals react with in the air to produce metal oxides?

  Oxygen
• What are oxidation and reduction reactions collectively called?

  Redox reactions
• What occurs during oxidation?


  Oxygen is added to an element or a compound
• What occurs during reduction?


  Oxygen is removed from an element or a compound
• What is the chemical equation for the reaction of copper metal with oxygen?

  2Cu + O ⟶ 2CuO
• In the reaction of copper with oxygen, what happens to the copper metal?


  Copper metal has been oxidised since oxygen has been added to it
• What is the chemical equation for the reaction of zinc oxide with carbon?

  ZnO + C ⟶ Zn + CO
• In the reaction of zinc oxide with carbon, what happens to the zinc oxide?


  Zinc oxide has been reduced since it has lost oxygen
• What happens to the carbon atom in the reaction of zinc oxide with carbon?


  The carbon atom has been oxidised since it has gained oxygen
• What are redox reactions characterized by?


  They are simultaneous reactions that occur at the same time
• What is the reactivity series of metals?


  • A list of metals arranged in order of their reactivity
  • Metals higher in the series lose electrons easily
  • Carbon and hydrogen are included for extraction processes
• What do metal atoms form when they react with other substances?


  Positive ions by loss of electrons
• What does a higher position in the reactivity series indicate about a metal?


  The metal is more reactive and loses electrons easily
• What mnemonic can help remember the order of metals in the reactivity series?


  "Please send lions, cats, monkeys and cute zebras into hot countries signed Gordon"
• What are the most reactive metals in the reactivity series?


  1. Potassium
  2. Sodium
  3. Lithium
  4. Calcium
  5. Magnesium
• What are the chemical properties of metals studied through?


  • Their reactions with water
  • Their reactions with dilute acids
• Which metals react with water?

  Metals above hydrogen in the reactivity series
• How do metals that react with cold water behave?


  They form a metal hydroxide and hydrogen gas
• What is the reaction of calcium with water?


  Ca + 2H₂O → Ca(OH)₂ + H₂
• How does magnesium react with cold water?

  Magnesium reacts very slowly with cold water when finely divided
• What does magnesium react with to form a metal oxide and hydrogen gas?


  Gaseous water
• What is the general reaction of metals with cold water summarized?


  Metal + water → metal hydroxide + hydrogen
• What is the summary of metals reacting with cold water?

  • Potassium: Reacts violently
  • Sodium: Reacts quickly
  • Lithium: Reacts less strongly
  • Calcium: Reacts less strongly
  • Magnesium: Reacts very slowly
  • Zinc, Iron, Copper: Generally unreactive
• Which group of metals is reactive with water?

  Group 1 metals
• Which group of metals is less reactive with water?

  Group 2 metals
• Which metals are generally unreactive with water?


  Other metals
• What do most metals react with?

  Dilute acids such as HCl
• Which metals do not react with acids?

  Metals below hydrogen in the reactivity series
• What happens when acids and metals react?


  The hydrogen atom in the acid is replaced by the metal atom
• What is the general reaction of metals with acids?


  Metal + acid → metal salt + hydrogen
• What is the chemical equation for the reaction of iron with hydrochloric acid?


  Fe + 2HCl → FeCl₂ + H₂
• What happens to metals during reactions with water and acids?


  Metals become positive ions
• How is the reactivity of metals related to their tendency to become ions?


  The more reactive the metal, the more easily it becomes an ion
• What is the role of carbon in the reactivity series?


  • Carbon is a cheap reducing agent
  • Used to remove oxygen from metal oxide ores
  • Metals below carbon can be extracted by heating with carbon
  • Metals above carbon require other extraction methods
• What are displacement reactions?


  • More reactive metal displaces a less reactive metal from its compounds
  • Occurs in reactions with metal oxides and aqueous solutions of metal compounds
• What is the equation for the reduction of copper(II) oxide by zinc?


  Zn + CuO → ZnO + Cu
• What is the thermite reaction?


  • A highly exothermic reaction
  • Occurs when iron(III) oxide reacts with aluminium
  • Iron is displaced due to aluminium's higher reactivity
  • Used in welding and incendiary devices
• What happens during the thermite reaction?


  Iron(III) oxide and aluminium react to produce iron and aluminium oxide
• What is the equation for the thermite reaction?


  Fe₂O₃ + 2Al → 2Fe + Al₂O₃
• How can the reactivity between two metals be compared?


  Using displacement reactions in salt solutions