Science Class Eight

Materials: Metals and Non-Metals

NCERT Solution - Part 1

1. Which of the following can be beaten into thin sheets?
(a) Zinc
(b) Phosphorus
(c) Sulphur
(d) Oxygen

Answer: - (a) Zinc

2. Which of the following statements is correct?
(a) All metals are ductile.
(b) All non-metals are ductile.
(c) Generally, metals are ductile.
(d) Some non-metals are ductile.

Answer: - (c) Generally, metals are ductile

3. Fill in the blanks :
(a) Phosphorus is very ………….non-metal.

Answer: Reactive

(b) Metals are …………..conductors of heat and …………..

Answer: Good, temperature

Answer: More

(d) Metals react with acids to produce …………..gas.

Answer: hydrogen

4. Mark ‘T’ if the statement is true and ‘F’ if it is false.
(a) Generally, non-metals react with acids. (F )
(b) Sodium is a very reactive metal. ( T)
(c) Copper displaces zinc from zinc sulphate solution. (F )
(d) Coal can be drawn into wires. ( F)
5. Some properties are listed in the following Table. Distinguish between metals and non-metals on the basis of these properties.

Answer:

Properties	Metals	Non-metals
Appearance	Lustrous	Dull
Hardness	Hard	Brittle
Malleability	Malleable	Non-malleable(Brittle)
Ductility	Ductile	Non-ductile(Brittle)
Heat conduction	Conductor	Non-conductor
Conduction of electricity	Conductor	Non-conductor