NCERT class 10 Science chapter 3 is about metals and non-metals. Prepare for your class 10 science exam by reviewing our lessons, note and model question papers.

Notes

Based on their properties, elements can be classified as metals and non-metals

Physical Properties of metals

In their pure state, metals have a shining surface. This property is called metallic lustre.

Metals are hard and cannot be cut easily. The hardness varies from metal to metal.

Some metals are malleable. They can be beaten into thin sheets.

Some metals are ductile. That means they can be drawn into thin wires.

Metals are good conductors of heat. They have very high melting points.

Metals produce a sound when they strike a hard surface. Such metals are called sonorous.

One mark questions

1. Which are the most malleable metals?

Gold and silver

2. Which is the most ductile metal?

Gold

3. Which metals are the best conductors of heat?

Silver and copper

4. Which of the following is a good conductor of heat?

a) lead; b) mercury; c) silver

Answer: silver

5. Which is the only non-metal that exists in liquid form?

Bromine

6. Name the metal which exists as a liquid at room temperature.

Mercury

7. Which metals have the lowest melting point?

Gallium and caesium

8. Name a non-metal that is lustrous.

Iodine

9. Diamond is an ………………………. of carbon.

Allotrope

10. Which is the hardest natural substance?

Diamond

11. Name a non-metal that can conduct electricity?

Graphite

12. Graphite is an allotrope of ……………………….

Carbon

13. When non-metals dissolve in water, they produce ………………………. oxides.

Acidic

14. Name the metal which is a liquid at room temperature

Mercury

15. Name some metals which can be cut with a knife.

Lithium, sodium and potassium

16. Name a metal which is the best conductor of heat

Silver / copper

17. Name two metals which are poor conductors of heat.

Lead and mercury

18. Which metal burns in air with a white flame?

Magnesium