CBSE Class 4 Science Evaporation Worksheet Set 02

Qn.1-Choose the correct option:

Question 1. The changing of a liquid into its vapour is called
a) boiling
b) evaporation
c) condensation
Answer: (b) evaporation
Evaporation is the process by which a liquid turns into a gas or vapour at temperatures below its boiling point.
In simple words: When a liquid turns into invisible gas and mixes into the air, it is called evaporation.

Exam Tip: Remember that evaporation happens at the surface of a liquid at any temperature, whereas boiling happens throughout the liquid at a specific temperature.

Question 2. The changing of a vapour into a liquid is called
a) boiling
b) evaporation
c) condensation
Answer: (c) condensation
Condensation is the process where water vapour in the air is cooled down and changes back into liquid water.
In simple words: When water vapour cools down and turns back into water drops, it is called condensation.

Exam Tip: Condensation is the exact opposite of evaporation. Look for cooling keywords when identifying condensation.

Question 3. Which of these can be compressed.
a) solids
b) liquids
c) gas
Answer: (c) gas
Gases have a lot of space between their particles, making them highly compressible compared to tightly packed solids and liquids.
In simple words: Gases can be easily squeezed into a smaller space because their particles are very far apart.

Exam Tip: Gases are compressible because their particles have large intermolecular spaces, unlike solids and liquids which have fixed volumes.

Question 4. Which of these can flow.
a) pencil
b) oil
c) perfume
Answer: (b) oil (Note: Perfume also flows, but oil is a standard primary liquid example in this context.)
Liquids and gases are fluids, meaning they have the ability to flow. Among the given options, oil is a liquid that flows easily.
In simple words: Liquids like oil can flow and take the shape of the container they are poured into.

Exam Tip: Substances that can flow are called fluids. Liquids and gases are both fluids, whereas solids maintain a fixed shape.

Qn 2. Given below are some materials. Mention whether they are solids or liquids.

Question a. plastic
Answer: Solid
In simple words: Plastic maintains its own fixed shape and size, so it is a solid.

Exam Tip: Hard and rigid materials that do not flow on their own are classified as solids.

Question b. oil
Answer: Liquid
In simple words: Oil flows and takes the shape of its container, so it is a liquid.

Exam Tip: Substances that flow and have no fixed shape of their own are liquids.

Question c. wood
Answer: Solid
In simple words: Wood is a hard material with a fixed shape, making it a solid.

Exam Tip: Natural materials like wood, rock, and metal are solid at room temperature.

Question e. kerosene
Answer: Liquid
In simple words: Kerosene is a fluid fuel that flows freely, so it is a liquid.

Exam Tip: All liquid fuels and water-like substances are classified as liquids.

Question f. milk
Answer: Liquid
In simple words: Milk is a drinkable fluid that flows, making it a liquid.

Exam Tip: Edible beverages and drinks are everyday examples of liquids.

Question g. iron rod
Answer: Solid
In simple words: An iron rod is hard, rigid, and keeps its shape, which means it is a solid.

Exam Tip: Metals in their rigid structural forms are always solids.