CBSE Class 9 Science Chapter 1 – Matter in Our Surroundings (Questions & Answers)
Are you searching for CBSE Class 9 Science Chapter 1 questions and answers? This page provides a complete, easy-to-read set of questions and answers for “Matter in Our Surroundings” based on the latest CBSE curriculum. Here, you’ll find accurate and simple explanations that cover key concepts like the classification of matter, its states (solid, liquid, gas), properties, and changes of state. Perfect for students across India looking to strengthen their understanding of this important chapter and score well in their CBSE Class 9 Science exam.
CBSE Class 9 Science Chapter 1: Matter in Our Surroundings
1 Questions & Answers
- Q1: What is matter?
Ans: Matter is anything that has mass and occupies space. It can be classified into three states: solid, liquid, and gas. - Q2: What is the difference between a solid and a liquid?
Ans: A solid has a fixed shape and volume due to strong intermolecular forces, while a liquid has a fixed volume but no fixed shape. - Q3: What is the process of sublimation?
Ans: The direct conversion of a solid into its vapour, without passing through the liquid state, is called sublimation. Example: dry ice. - Q4: Why can gases be compressed easily?
Ans: Gases have a lot of space between their particles, making it easy to compress them. - Q5: What is condensation?
Ans: The process by which gas changes into a liquid upon cooling is called condensation.
2 MCQs
- The state of matter with a fixed shape and volume is:
- a) Solid Ans
- b) Liquid
- c) Gas
- d) Plasma
- What is the SI unit of pressure?
- a) Newton
- b) Pascal Ans
- c) Joule
- d) Kelvin
- Which state of matter has the highest compressibility?
- a) Solid
- b) Liquid
- c) Gas Ans
- d) Plasma
- The process of converting a gas into a liquid is called:
- a) Evaporation
- b) Condensation Ans
- c) Sublimation
- d) Diffusion
- Which of the following is an example of sublimation?
- a) Ice melting
- b) Naphthalene balls disappearing Ans
- c) Water boiling
- d) Steam condensing
3 Important Questions
- What are the characteristics of matter?
- What is diffusion and how does it occur in gases?
- What are the differences between solids, liquids, and gases?
- Explain the process of condensation with an example.
- What is the effect of heating and cooling on gases?
- Define and give examples of sublimation.
4 Summary Table
| Property | Solid | Liquid | Gas |
|---|---|---|---|
| Shape | Fixed | No fixed shape, takes shape of container | No fixed shape |
| Volume | Fixed | Fixed | No fixed volume |
| Density | High | Medium | Very low |
| Compressibility | Very low | Low | Very high |
| Diffusion Rate | Very low | Moderate | Very high |
| Intermolecular Forces | Very strong | Moderate | Very weak |