CBSE Class 3 Moral Science Worksheet Set 02

Q.1 Fill in the blanks.

(1) Water vapour is the gaseous form of water.
Answer: Water vapour
In simple words: Water exists as a gas called water vapour in the air.

Exam Tip: Remember the three states of water: solid (ice), liquid (water), and gas (water vapour).

(2) Water is found in three forms.
Answer: three
In simple words: Water can be solid, liquid, or gas.

Exam Tip: State the exact number of forms when asked about states of water.

(3) When we cool water vapour it changes into water.
Answer: cool
In simple words: Cooling gas turns it back into liquid water.

Exam Tip: This process of cooling gas to form liquid is called condensation.

(4) Ice is lighter than water.
Answer: Ice
In simple words: Solid water floats on liquid water because it is less dense.

Exam Tip: This is why ice cubes float in a glass of juice or water.

(5) The change of a substance from the vapour state to a denser liquid or solid state is called condensation.
Answer: change
In simple words: Gas turning into liquid or solid is condensation.

(6) Liquid has no fixed shape.
Answer: Liquid
In simple words: Liquids take the shape of the container they are poured into.

Exam Tip: Liquids have a fixed volume but no fixed shape.

(7) Substance which has a certain shape, volume and hardness is called solid.
Answer: solid
In simple words: Solids are hard and keep their own shape.

Exam Tip: Solids have both fixed shape and fixed volume.

(8) Hydrogen and oxygen gases make water.
Answer: Hydrogen, oxygen
In simple words: Water is made by combining two gases: hydrogen and oxygen.

Exam Tip: The chemical formula of water is H2O, showing it contains hydrogen and oxygen.

(9) Air cannot be seen.
Answer: Air
In simple words: We cannot see air, but we can feel it when it blows.

Exam Tip: Air is a mixture of transparent gases.

Q.2 Solve and find 6 sources of water.

Question 2. Solve and find 6 sources of water from the given grid.
Answer:

In simple words: The six sources hidden in the puzzle are Ocean, Rain, Lake, River, Pond, and Well (or Spring).
Exam Tip: Look carefully across rows, columns, and diagonals to locate word search terms.

Q.3 Answer the following.

Question 3.(1) Define (i) Evaporation (ii) Solid.
Answer: (i) Evaporation: The process by which liquid changes into water vapour (gas) on heating.
(ii) Solid: A substance that has a definite shape, fixed volume, and is hard.
In simple words: Evaporation turns water into gas, while a solid is a hard object that keeps its shape.

Exam Tip: Learn exact scientific definitions for key terms like evaporation and solid.

Question 3.(2) Which two gases make water?
Answer: Hydrogen and oxygen gases combine to make water.
In simple words: Water is formed by hydrogen and oxygen.

Exam Tip: Remember the chemical constituents of water: Hydrogen and Oxygen.

Question 3.(3) How will you make ice from water?
Answer: We can make ice from water by keeping water in the freezer of a refrigerator so that it freezes into a solid.
In simple words: Freeze liquid water to turn it into ice.

Exam Tip: Cooling liquid water below 0 degrees Celsius changes it into ice.

Q.4 State whether the following statements are true or false.

Question 4.(1) We can see, feel & taste water.
Answer: False
In simple words: Pure water has no color, taste, or odor, so we cannot see or taste it directly in the air, though we can feel it.

Exam Tip: Pure water is colorless, tasteless, and odorless.

Question 4.(2) The three forms of water can be changed from one to another.
Answer: True
In simple words: Ice can melt into water, and water can evaporate into vapour.

Exam Tip: States of water are interconvertible by heating or cooling.

Question 4.(3) Ice has no fixed shape.
Answer: False
In simple words: Ice is a solid and has a fixed shape.

Exam Tip: Solids always maintain a fixed shape and volume.

Question 4.(4) Substance which has a certain shape, volume and hardness is called liquid substance.
Answer: False
In simple words: A substance with a fixed shape, volume, and hardness is a solid, not a liquid.

Exam Tip: Liquids do not have a fixed shape or hardness.

Question 4.(5) Evaporation takes place only once in a while.
Answer: False
In simple words: Evaporation is a continuous process happening whenever water is exposed to heat.

Exam Tip: Evaporation happens constantly in nature from oceans, rivers, and puddles.

Question 4.(6) Ice removed from the freezer and placed in open melts.
Answer: True
In simple words: Ice melts into liquid water when exposed to warmer room temperatures.

Exam Tip: Heat causes solids to melt into liquids.

Question 4.(7) Ice is heavier than water.
Answer: False
In simple words: Ice is lighter than water, which is why it floats.

Exam Tip: Less dense objects float on denser fluids.

Question 4.(8) Water vapour is the liquid form of water.
Answer: False
In simple words: Water vapour is the gaseous form of water.

Exam Tip: Liquid water is the liquid form; water vapour is the gas.

Q.5 Match the following.

Question 5. Match the following correctly:
(1) Ice - (b) solid
(2) Water - (d) liquid
(3) Water Vapour - (a) gas
(4) \(H_2O\) - (c) water
Answer: (1) - (b), (2) - (d), (3) - (a), (4) - (c)
In simple words: Match each state of water and its formula to its correct description.

Exam Tip: Double-check matching items to avoid silly mistakes.

Q.6 Name the forms of water.

Question 6. Name the forms of water shown in the diagrams.
Answer: First diagram (Ice cube tray): Solid form (Ice)
Second diagram (Glass of water): Liquid form (Water)
In simple words: The first picture shows solid ice cubes, and the second picture shows liquid water.

Exam Tip: Identify everyday items as representations of states of matter.