Chapter 1: Matter in our surroundings- Exercise- 1

 Science

(www.olympiadsuccess.com)

Chapter 1: Matter in our surroundings

Class: IX

Exercise number 1

Question 1

Which of the following is matter?

Chair, air, love, smell, hate, almonds, thought, cold, cold drink, smell of perfume.

Answer 1

Any substance that occupies space and having mass is called matter. The matter can exist in three different states. They are solid, liquid, and gaseous.

Examples of solid state - chair, almonds

Liquid state - cold drink

Gaseous state - air, smell of perfume

Note The sense of smell can't be considered as matter. However, the smell or odour of a substance can be classified as matter. We can say that the smell of any substance is the gaseous form of that substance and even its very low concentrations can be detected by our olfactory system. Hence, we can say that the smell of perfume is matter.

Question 2

Give reasons for the following observation

The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close.

Answer 2

As temperature increases, the rate of diffusion of the solid particles into the air also increases and this is due to an increase in the kinetic energy of the solid particles. This is why the smell of hot sizzling food reaches us several metres away, but to get the smell from cold food we have to go close.

Question 3

A diver is able to cut through water in a swimming pool. Which property of matter does this observation show?

Answer 3

The ability of a diver to cut through water in a swimming pool shows that matter is made up of particles and they have space between them.

Question 4

What are the characteristics of particles of matter?

Answer 4

The characteristics of particles of matter are

• Particles of matter have spaces between them.
• They are continuously moving.
• Particles attract each other.