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• Properties of metals and nonmetals:
  

  Property	Metals	Nonmetals
  Lustre [shine]	Have lustre	Do not have lustre
  Hardness	Are hard	Are soft
  Malleability [beaten into sheet]	Are malleable	Do not have property of malleability
  Ductility [drawn into wires]	Are ductile	Do not have property of ductility
  Sonorous [produce sound]	Are sonorous	Not sonorous
  Heat conduction	Good conductor of heat	Bad conductor of heat
  Electricity conduction	Good conductor of electricity	Bad conductor of electricity

• Exception in metals and non metals:
  • Among metals, sodium and potassium are soft.
  • All metals are solid, only mercury is liquid metal
  • Among non metals, Iodine is lustrous
  • Hardest substance diamond is non metal
• Chemical properties of metals and nonmetals:
  • Reaction of metals with oxygen
    • Oxygen + Metals ⟶ Metal Oxide
    • E.g. Iron if exposed to air and water forms is iron oxide (rust).
    • Iron (Fe) + Oxygen (O₂) + Water (H₂O) → Rust (Fe₃O₄) + Hydrogen (H₂)
  • Reaction of nonmetals with oxygen
    • Oxygen + Non metals ⟶ Acidic oxides
    • E.g. Sulphur in air forms sulphur dioxide. It dissolves in water forming sulphurous acid.
    • Sulphur (S) + Oxygen (O₂) → SO₂
    • Sulphur dioxide (SO₂) + Water (H₂O) → Sulphurous acid (H₂SO₃)
  • Reaction of metals and non metals with water
    • Metals react with water to form alkaline solution with release of energy in the form of heat
    • Non metals do not react with water
  • Metals react with acids to form hydrogen gas
    • Metals + Acids ⟶ Hydrogen gas
  • Non metals do not react with acids.
  • Reactivity of metals and non metals with bases
    • Metals react with bases produces hydrogen gas
    • Reaction of nonmetals with bases are complex
  • Displacement reaction : It is displacement of one metal from another metal from its compound in aqueous solution. It is represented as
    XY + Z ⟶ ZY + X
    E.g. CuSO₄ + Zn→ ZnSO₄ + Cu
• Uses of metals
  • Iron is used for making utensils, pipes, gates, agricultural equipments, iron nails, etc
  • Copper is used to make electric wires, alloys, utensils and in process of electroplating
  • Aluminium is used for making electric wires, aircraft parts, alloys, paints, etc.
  • Gold and silver is used to make gift coins and jewellery. Silver is used in making high reflecting mirrors, solar cells, decoration of sweets, etc
• Uses of non metals
  • Oxygen is necessary for the process of respiration and combustion reactions
  • Nitrogen is used to prepare fertilizers
  • Chlorine is used in water purification, chlorine compounds (bleaching powder) is used for cleaning purposes in textile industry, cloths, wool, etc.
  • Red phosphorus is used in the manufacture of match sticks and firecrackers.
  • Solution of iodine in alcohol (tincture iodine) is used as an antiseptic and in healing wounds.