CBSE Class 9 Science Important Questions

Here are 10 important questions from Class 9 Science chapters that will help you prepare effectively and understand the concepts better.

1. What does matter? Give examples.

Ans: Matter is anything that has mass and occupies space. It includes solids, liquids, and gases. For example, a chair is a solid (it has a fixed shape), water is a liquid (it takes the shape of its container), and air is a gas (it has no fixed shape and can expand). Matter can exist in different states, and each state has unique properties.

2. What is the law of conservation of mass?

Ans: The law of conservation of mass states that mass can neither be created nor destroyed in a chemical reaction. This means that the total mass of the reactants (the substances that react) is equal to the total mass of the products (the substances formed). For example, if you burn a piece of wood, the mass of the ash and gases produced will equal the mass of the original wood.

3. What are the different states of matter?

Ans: The three primary states of matter are solids, liquids, and gases. Solids have a definite shape and volume because their particles are closely packed together. Liquids have a definite volume but take the shape of their container as their particles are less tightly packed. Gases have neither a definite shape nor volume, as their particles are spread far apart and move freely.

4. Explain the process of photosynthesis.

Ans: Photosynthesis is the process by which green plants make their food using sunlight, carbon dioxide, and water. In this process, chlorophyll (a green pigment in plants) captures sunlight, which is then used to convert carbon dioxide from the air and water from the soil into glucose (a type of sugar) and oxygen. The overall reaction can be simplified as: Carbon dioxide + Water + Sunlight → Glucose + Oxygen.

5. What are acids and bases? Give examples.

Ans: Acids are substances that taste sour and turn blue litmus paper red. They release hydrogen ions (H⁺) in solution. Examples include hydrochloric acid (found in stomach) and citric acid (found in lemons). Bases, on the other hand, taste bitter and turn red litmus paper blue. They release hydroxide ions (OH⁻) in solution. Examples include sodium hydroxide (used in soap) and baking soda.

6. What is the difference between a physical change and a chemical change?

Ans: A physical change alters the form or appearance of a substance without changing its chemical composition. Examples include melting ice or boiling water. A chemical change, however, involves a transformation that changes the chemical composition of a substance, resulting in new products. For instance, burning wood produces ash and gases, which are different from the original wood.

7. Describe the structure of an atom.

Ans: An atom is the basic unit of matter and consists of a nucleus surrounded by electrons. The nucleus contains protons (which have a positive charge) and neutrons (which have no charge). Electrons (which have a negative charge) orbit the nucleus in energy levels. The number of protons determines the element, while the arrangement of electrons affects how the atom interacts with other atoms.

8. What are natural resources? Classify them.

Ans: Natural resources are materials or substances found in nature that can be used for economic gain. They are classified into renewable and non-renewable resources. Renewable resources, like sunlight, water, and wind, can be replenished naturally. Non-renewable resources, such as coal, oil, and natural gas, exist in finite amounts and cannot be replaced once depleted.

9. What is force? Explain its types.

Ans: Force is a push or pull acting on an object that can change its state of motion or shape. There are two main types of forces: contact forces and non-contact forces. Contact forces, like friction and tension, occur when objects are in contact. Non-contact forces, like gravitational and magnetic forces, act at a distance without physical contact.

10. What is the significance of the periodic table?

Ans: The periodic table is a systematic arrangement of elements based on their atomic number and properties. It helps scientists understand the relationships between different elements and predict their behaviour. The table organises elements into groups with similar properties, making it easier to study and identify patterns in chemical behaviour and reactions.

Here are some important questions for Class 9 Science. Check the Chapter-wise Important Questions table for a better understanding of each chapter. This table will help you understand the main ideas and prepare well for your exams.

How do Science Important Questions Class 9 Help you with Exams?

• Class 9 Science Important Questions help you focus on key topics, making it easier to target your revision. They clarify difficult concepts, strengthening your understanding of the subject. 

• Practising these questions familiarises you with the exam format and types of questions. This preparation improves your time management skills during the exam. 

• Answering important questions improves your confidence, making you feel more prepared on exam day. They also help you identify weak areas that need more attention for effective studying. 

• These questions serve as a quick revision tool, allowing you to review key concepts before the exam. Engaging with them enhances memory retention, making it easier to recall information during the test.

Vedantu's Important Questions for CBSE Class 9 Science are a valuable resource for students. They help you focus on the main topics and understand key concepts clearly. By practising these questions, you can gain confidence and improve your exam preparation. Using this guide will make your studying more effective and help you perform better in your exams. 

Additional Study Materials for Class 9 Science