NCERT Class VIII Science Solutions: Chapter 4-Materials: Metals and Non-Metals Part 1

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Question 1:

Which of the following can be beaten into thin sheets?

  1. Zinc

  2. Phosphorus

  3. Sulphur

  4. Oxygen

Answer:

A. Zinc

As Zinc is a metal and metal has property of malleability (Can be converted in sheet by beating). Rest of these are non-metals.

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Result for Zinc

Image result for zinc

Question 2:

Which of the following statements is correct?

  1. All metals are ductile.

  2. All non-metals are ductile.

  3. Generally, metals are ductile.

  4. Some non-metals are ductile.

Answer:

C. Generally, metals are ductile.

Mercury (metal) is liquid at room temperature and cannot be drawn into wires. Therefore, it is non-ductile. So the option (a) is incorrect. Not a single non-metal is ductile, so option (b) and (d) are incorrect.

Image result for metals are ductile.

Metals Are Ductile.

Image result for metals are ductile.

Question 3:

Fill in the blanks:

  1. Phosphorus is very ___________ non-metal.

  2. Metals are ___________ conductors of heat and ___________.

  3. Iron is ___________ reactive than copper.

  4. Metals react with acids to produce ___________ gas.

Answer:

  1. Phosphorus is very reactive non-metal.

  2. Metals are good conductors of heat and electricity.

  3. Iron is more reactive than copper.

  4. Metals react with acids to produce Hydrogen gas.

Question 4:

Mark ‘T’ if the statement is true and ‘F’ if it is false.

  1. Generally, non-metals react with acids. ( )

  2. Sodium is a very reactive metal. ( )

  3. Copper displaces zinc from zinc sulphate solution. ( )

  4. Coal can be drawn into wires. ( )

Answer:

Generally, non-metals react with acids. (False)

  • Generally, metals react with acids and release gas.

  • Sodium is a very reactive metal. (True)

  • Sodium, Potassium, Calcium etc., are very reactive metals.

  • Copper displaces zinc from zinc sulphate solution. (False)

  • The reactivity of zinc is higher than copper. So, copper cannot displace zinc from zinc sulphate solution.

  • Coal can be drawn into wires. (False)

  • Coal is a non-metal, so it is non ductile.