Introduction

Every little thing in the universe is made up of materials called "matters"."Matter" is anything that has mass and occupies space. Early Indian philosophers classified matters in the form of five essential elements called the 'Panch Tatva': air, water, earth, fire and sky. According to them, every living or non-living thing is made up of these five primitve elements.

Examples:

Cloud Stone

Plants Food

In modern times, scientists classifiesd matters based on their physical and chemical properties. In this chapter, we are dealing with only physical properties. Let's take a look.

Matter is made up of particles

When we dissolve a substance in water, the particles of the substance get into the space between the molecules of water. The particles of matter are tiny. When we dilute coloured water, with every dilution, though the colour becomes lighter, it is still visible. The particles of matter are small beyond our imagination.

Lets' do an activity to show that matter is composed of smaller particles.

Activity

Equipments required: 100 ml beaker, salt/sugar, water, and a glass rod.

Step 1: Take a 100 ml beaker, fill half the beaker with water, and mark the level.

Step 2: Add some sugar or salt to the beaker and dissolve it with the help of a glass rod.

Step 3: observe the changes that take place in the beaker.

Questions:

Q1: What do you think has happened to the salt?

Ans: Salt is dissolved in water.

Q2: Where does it disappear?

Ans: Particles of salt get into the spaces between particles of water.

Q3: Does the level of water change?

Ans: No, there is no change in the level of water.

Conclusion: From this activity, we can conclude that matter is made up of small particles. And there is space between these particles.

How small are these particles of matter?

The matter is made up of very small particles.

Consider an activity.

Activity

Equipment required: Crystals of potassium permanganate, water.

Step 1: Take 2-3 crystals of potassium permanganate and dissolve them in 100 ml of water.

Step 2: Take out approximately 10 ml of this solution and put it into 90 ml of clean water.

Step 3: Take out 10 ml of this solution and put it into another 90 ml of clean water.

Step 4: Keep diluting the solution for about 5 to 8 times.

Is the water still coloured?

Yes, the water is still coloured.

From the experiment, it is concluded that a few crystals of potassium permanganate can colour a large volume of water. This is because matter is made of very small particles, which are spread in the water.