Class 7 Science Chapter 5: Changes Around Us: Physical and Chemical — practice questions with answers
Free practice for Class 7 Science, Chapter 5: Changes Around Us: Physical and Chemical. Try the solved questions below, then take a free test with instant marking and explanations.
30 questions12 easy, 15 medium, 3 hardNCERT · CBSE · State boards
Sample questions with solutions
Q1. Folding paper into a boat and unfolding it gives the same paper back. This is a ______ change.
- physical
- chemical
- permanent
- harmful
Show answer
Answer: A. physical
Why: The substance changes in appearance but remains the same — a physical change. [p.59]
Why: The substance changes in appearance but remains the same — a physical change. [p.59]
Q2. Crushing chalk into powder changes its size and shape. Is a new substance formed?
- No — it is still chalk, a physical change
- Yes — a chemical change
- Yes — it becomes lime water
- It becomes rust
Show answer
Answer: A. No — it is still chalk, a physical change
Why: Crushing changes appearance but not the substance. [p.59]
Why: Crushing changes appearance but not the substance. [p.59]
Q3. Changes in which one or more new substances are formed are called ______ changes.
Show answer
Answer: chemical
Why: New substances form through a chemical reaction. [p.60]
Why: New substances form through a chemical reaction. [p.60]
Q4. Lime water turning milky is used as a test for which gas?
- Carbon dioxide
- Oxygen
- Nitrogen
- Hydrogen
Show answer
Answer: A. Carbon dioxide
Why: The milkiness of lime water tests for carbon dioxide. [p.61]
Why: The milkiness of lime water tests for carbon dioxide. [p.61]
Q5. Vinegar and baking soda fizz and the gas turns lime water milky. What is the gas?
- Carbon dioxide
- Oxygen
- Water vapour
- Chlorine
Show answer
Answer: A. Carbon dioxide
Why: The fizzing gas is carbon dioxide. [p.61]
Why: The fizzing gas is carbon dioxide. [p.61]
Q6. Burning a magnesium ribbon forms magnesium oxide and gives out heat and light. What kind of change is it?
- Chemical
- Physical
- Neither
- Reversible
Show answer
Answer: A. Chemical
Why: A new substance forms, along with heat and light. [p.62]
Why: A new substance forms, along with heat and light. [p.62]
Practise all 30 questions free
Timed test, marked instantly, with the correct answer and explanation for every question and a chapter-wise report.
Start the free testUnderstand it by doing
Try the interactive Science Lab for Class 7.
Frequently asked questions
How many practice questions are there for Class 7 Science Chapter 5: Changes Around Us: Physical and Chemical?
30 questions (12 easy, 15 medium, 3 hard). A few are solved on this page; the free test shows the answer and explanation for every question after you submit.
Is this chapter from the NCERT book?
Yes — it follows the NCERT Class 7 Science syllabus, used by CBSE and many state boards.