States of Matter (Term 1 Chapter 2 | 3rd Science)
I. Indicate whether the following statements are true or false.
1. Solids have a definite volume. (True)
2. Liquids can not flow. (False)
3. We can melt any substance by cooling it. (False)
4. Liquids can take the shape of the container. (True)
5. Gases have a definite shape or volume. (False)
6. Matter changes its state when heat is added or removed. (True)
7. A fuel is a substance which gives heat energy on burning. (True)
II. Fill in the blanks. (Evaporation, Mass, Water, Solid, Stone, Freezing)
1. The measure of matter in an object is called Mass.
2. Change of liquid into vapour on heating is called Evaporation.
3. An example for liquid is Water.
4. The change of liquid into solid on cooling is known as Freezing.
5. An example for solid is Stone.
III. Draw a line to match the objects and their state of matter.
IV. Answer in a word or two.
1. Which of these is a solid: wood or juice?
Answer : Wood.
2. Which of these is hard : a sponge or a glass or a cloth?
Answer : a glass.
3. What are three states of matter?
Answer : Solid , Liquid, Gas.
4. Name three substances which can change to liquid when they are heated?
Answer : Ice, Cheese, Jaggery.
5. In which state of matter the particles are very close to each other?
Answer : Solid State.
6. What state of matter is rain?
Answer : Liquid state
7. Which among the state of matter has definite size but no definite shape?
Answer : Liquid state
8. What would cause a liquid to turn into a solid?
a) Pouring it into a container
b) Heating it until it boils
c) Cooling it until it freezes
d) Keeping its temperature the same
Answer : c) Cooling it until it freezes
9. What are some properties of pencil?
* Pencil is rigid
* It has definite shape and volume.
* It occupies a fixed space.
V. Find me. ( Liquid, Water, Wood)
1. I am a five letter word. I am an essential need for your life. I remain in all the three states of matter. Who am I ?
Answer :I am water.
2. I am a solid. I am obtained from the trees. I am useful for heating. Who am I?
Answer :I am wood.
3. I am one among the three states. I have loosely arranged particles. I become vapour on heating. Who am I ?
Answer :I am liquid.
VI. Describe the word in one sentence.
* Solids are things that have definite shape and volume.
* Liquids are things that do not have a definite shape but occupies space.
* Change of solid into liquid on heating is called melting.
* Change of liquid into vapour on heating is called evaporation.
* Change of liquid into solid on cooling is known as freezing.
VII. Which change of state is taking place in each description below? Use these words.
Freezing, Evaporation, Condensation, Melting
a) An ice cube turning to water Melting
b) Water turning to ice in a freezer Freezing
c) Change of liquid into vapour on heating Evaporation
d) A bathroom mirror misting up Condensation
Let us Do
List out the some of the matter around you.
Answer: 1. Book 2.Table 3.Cloud 4. Tree
Let us Do
1. Place 4 1L bottles of different shapes on the table.
2. Take a bucket with water.
3. Call one child to hold the empty bottles and the other to fill water into them using a paper cup.
4. Ask the other children to fill the table as given below.
Did each bottle need the same number of cups to get filled?
We can see that water takes up the same space in each bottle and the shape of the water is same as the shape of the bottle.
1. What is the shape of water in your bottle?
The water takes up the shape of my bottle.
2. What happens if you pour water on the floor or table?
The water flours.
Cooking gas in gas-cylinder has a smell. Why?
Because Ethyl mercaptan is added with LPG to find the leakage.
Let us Do
Say whether it is Solid or Liquid or Gas (Put ‘S’ for Solid, ‘L’ for Liquid and ‘G’ for Gas).
Let us Read and Complete the table
Here are some properties of matter:
Fixed shape, No fixed shape, Fixed volume, No fixed volume, Flow all sides, Rigid
Copy the following table. Write each property in the correct column of the table. Some properties may belong to more than one column.
Let us Do
* Take some ice cubes in a container. Heat the container and observe the changes.
Ice cubes melt.
* Take some cheese in a container. Heat the container and observe the changes.
* Take some jaggery in a pan. Heat the pan and observe the changes.
Let us think
What makes the coconut oil freeze in winter season?
In winter season room temperature will drop down almost below 20°C which is less than the freezing point of coconut oil. So it freeze in winter season.
Complete the table
Think and answer
One of these cans was in the fridge and the other was not.
a) Which can was taken from the fridge?
b) How do you know?
Water droplets appear on the can A.
c) How did water droplets appear on the can A?
Because of condensation.
d) Why are there no water droplets on can B?
Can B is not kept in the fridge.
Let us Understand
* Keep a stone on the floor. Does it move by itself?
* Pour a mug of water on the floor. Does the water flow? Does it flow in one direction?
Yes, the water flows. It flows in all direction.
* Take an air filled balloon. Prick it with a needle. Does the air rush out?
* Fill an open vessel with water. Press the surface of the water with your hands. How do you feel?
Look at the pictures. Write down what you see.
(Wood, Leaves, Paper)
Match the following.