Physical and Chemical Changes
14 solved questions from Class 7 Science, each with the full working. Tap any question to see the step-by-step solution.
- 1 What is the fundamental scientific concept introduced in the chapter 'Physical and Chemical Changes'? medium MCQ Key Concept & Definition
- 2 Which of the following is an important application or observation related to 'Physical and Chemical Changes'? easy MCQ Practical Application
- 3 What primary question does the chapter 'Physical and Chemical Changes' aim to answer? medium MCQ Core Scientific Inquiry
- 4 Why is the study of 'Physical and Chemical Changes' essential for students in class-7? hard MCQ Importance & Significance
- 5 Which key practice is recommended while studying topics in 'Physical and Chemical Changes'? medium MCQ Scientific Method
- 6 What is the primary topic or theoretical principle explored in 'Physical and Chemical Changes' (Class 7 SCIENCE)? medium MCQ Chapter Core Principle
- 7 Which key mechanism or analytical rule is highlighted in 'Physical and Chemical Changes'? medium MCQ Key Analytical Mechanism
- 8 Explain the difference between a physical change and a chemical change. Give two examples of each and justify your choices. hard 5 marks Distinguishing physical and chemical changes
- 9 A piece of iron is left outside and after a few weeks it turns brown. Is this change physical or chemical? Explain. easy 2 marks Identifying chemical change by formation of new substance
- 10 Which of the following changes is a chemical change? 1) Melting ice 2) Burning of paper 3) Dissolving sugar in water 4) Boiling water medium MCQ 3 marks Recognising chemical changes among common processes
- 11 A 200 g piece of iron is placed in a sealed container containing 1 L of water. After 3 days the iron turns reddish‑brown. Explain whether this is a physical or chemical change, and give two other examples of similar changes. medium 3 marks Chemical change indicators
- 12 A candle is lit and the wax melts, but the chemical composition of the wax remains unchanged. This is an example of: 1. Physical change 2. Chemical change 3. Both 4. None easy MCQ 4 marks Physical change identification
- 13 In a laboratory, 8.0 g of zinc metal reacts completely with excess hydrochloric acid. Find the mass of hydrogen gas produced. hard 5 marks Stoichiometry of metal‑acid reaction
- 14 Identify the key indicators that distinguish a chemical change from a physical change. Provide at least three indicators. hard 5 marks Indicators of chemical change