Class 10 Chemistry



Metals and Non-metals

NCERT Exercise Solutions

Which of the following pairs will give displacement reactions?

  • NaCl solution and copper metal
  • MgCl2 solution and aluminium metal
  • FeSO4 solution and silver metal
  • AgNO3 solution and copper metal.
    Answer: (d) AgNO3 solution and copper metal.

Which of the following methods is suitable for preventing an iron frying pan from rusting?

  • Applying grease
  • Applying paint
  • Applying a coating of zinc
  • All of the above.
    Answer: (c) Applying a coating of zinc

An element reacts with oxygen to give a compound with a high melting point. This compound is also soluble in water. The element is likely to be

  • Calcium
  • Carbon
  • Silicon
  • Iron
    Answer: (a) Calcium

Food cans are coated with tin and not with zinc because

  • zinc is costlier than tin.
  • zinc has a higher melting point than tin.
  • zinc is more reactive than tin.
  • zinc is less reactive than tin.
    Answer: (c) zinc is more reactive than tin.

You are given a hammer, a battery, a bulb, wires and a switch.

  • How could you use them to distinguish between samples of metals and non-metals?

    Answer: If a substance can be beaten into thin sheets with the help of a hammer then the given substance is a metal. Otherwise, it is a non-metal. A circuit is made with the help of a battery, a bulb, wires and a switch. After that, the given substance is connected in the circuit. If the given substance ensures that the circuit is complete then it is a metal; else it is a non-metal.
  • Assess the usefulness of these tests in distinguishing between metals and non-metals.

    Answer: When a substance fulfills both the criteria then it can be confirmed as a metal. We know that some of the metals are brittle and graphite (a non-metal) is a good conductor of electricity. Hence, either of the tests cannot confirm a metal or non-metal; when the test is done in isolation.

What are amphoteric oxides? Give two examples of amphoteric oxides.

Answer: Some oxides show both acidic and basic characters. Such oxides are called amphoteric oxides. Amphoteric oxide reacts with acid as well as with base to form salt.

Example: Aluminium oxide and zinc oxide are examples of amphoteric oxide. When aluminium oxide reacts with a base, it gives salt and water.

Al2O3 + 2NaOH ⇨ 2NaAlO2 + H2O

When aluminium oxide reacts with an acid it gives salt and water.

Al2O3 + 6HCl ⇨ 2AlCl3 + 3H2O




In Text Solution 1

In Text Solution 2

Exericse Solution 2

Exericse Solution 3

Exemplar Solutions

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