Physical and Chemical change
📌 What is a Physical Change?
A physical change is a change in which only the physical properties (shape, size, state) of a substance change, but no new substance is formed.
👉 In simple words: The substance remains the same, only its appearance changes.
📌 What is a Chemical Change?
A chemical change is a change in which a new substance is formed with different properties.
👉 In simple words: The original substance changes completely into something new.
🧠 Key Differences Between Physical and Chemical Change
| Basis | Physical Change | Chemical Change |
|---|---|---|
| Definition | Change in physical properties only | New substance is formed |
| Nature | Temporary | Permanent |
| Reversibility | Usually reversible | Usually irreversible |
| Energy Change | Very little | Often involves heat, light, or gas |
| New Substance | Not formed | Formed |
| Example | Melting of ice | Burning of paper |
🔗 Related Topics: States of Matter, Chemical Reactions and Equations, Properties of Matter
🔍 Examples of Physical and Chemical Changes
🟢 Physical Changes
- Melting of ice
- Boiling of water
- Cutting paper
- Dissolving sugar in water
🔴 Chemical Changes
- Burning of wood
- Rusting of iron
- Cooking food
- Digestion of food
⚙️ Characteristics of Physical Change
- 🔸 No new substance is formed
- 🔸 Usually reversible
- 🔸 Only physical properties change
- 🔸 Energy change is minimal
⚙️ Characteristics of Chemical Change
- 🔸 New substance is formed
- 🔸 Usually irreversible
- 🔸 Chemical properties change
- 🔸 Energy is absorbed or released
- 🔸 Often involves color, smell, or gas change
📊 Real-Life Applications
- 🏠 Cooking food (Chemical change)
- 🧊 Ice melting (Physical change)
- 🏭 Industrial chemical reactions
- 🌍 Rusting affecting bridges and metals
❗ Important Notes (Exam-Oriented)
- ⭐ Rusting is always a chemical change
- ⭐ State change (solid → liquid → gas) is physical
- ⭐ Burning is always a chemical change
- ⭐ Dissolving can be tricky (usually physical)
❓ FAQs on Physical and Chemical Change
Q1. What is a physical change?
👉 A change where no new substance is formed.
Q2. What is a chemical change?
👉 A change where a new substance is formed.
Q3. Is melting of ice a chemical change?
👉 No, it is a physical change.
Q4. Why is rusting a chemical change?
👉 Because iron forms a new substance called rust.
Q5. Is cooking food reversible?
👉 No, it is a chemical change and irreversible.
📝 Practice Questions (With Answers)
Q1. Define physical change.
👉 Answer: A change in which only physical properties change and no new substance is formed.
Q2. Give two examples of chemical change.
👉 Answer: Burning of paper, rusting of iron.
Q3. Why is boiling water a physical change?
👉 Answer: Because no new substance is formed.
Q4. Differentiate between physical and chemical change.
👉 Answer: Physical change does not form new substance, chemical change does.
Q5. Why is chemical change important?
👉 Answer: It helps in forming new substances useful in daily life and industries.
🧠 MCQ Questions (Test Yourself)
1. Which of the following is a physical change?
A) Burning wood
B) Rusting iron
C) Melting ice
D) Cooking food
👉 Answer: C
2. Chemical change involves:
A) No new substance
B) Only size change
C) Formation of new substance
D) No energy change
👉 Answer: C
3. Which is a chemical change?
A) Cutting paper
B) Boiling water
C) Burning paper
D) Melting wax
👉 Answer: C
4. Physical changes are usually:
A) Permanent
B) Irreversible
C) Reversible
D) Chemical
👉 Answer: C
5. Rusting of iron is a:
A) Physical change
B) Chemical change
C) Temporary change
D) Reversible change
👉 Answer: B
6. Which of the following is NOT a physical change?
A) Freezing water
B) Dissolving sugar
C) Burning coal
D) Melting ice
👉 Answer: C
7. In chemical change, energy is:
A) Not involved
B) Always destroyed
C) Absorbed or released
D) Constant
👉 Answer: C
8. Which is reversible?
A) Cooking food
B) Rusting
C) Melting ice
D) Burning
👉 Answer: C
9. Formation of gas indicates:
A) Physical change
B) Chemical change
C) Temporary change
D) No change
👉 Answer: B
10. Which is an example of physical change?
A) Digestion
B) Cooking
C) Cutting wood
D) Burning fuel
👉 Answer: C
Read More Notes :
What is Decomposition reaction?
What is Rancidity? | Definition, Examples, Prevention & Explanation (Class 9–10 Science)
what is physical change with examples
Difference Between Oxidation and Reduction | Definition, Examples & Explanation (Class 9–10 Science)
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Difference between physical and chemical change
Chemical Reactions and Equations
Types of Chemical Reactions | Definition, Examples & Explanation
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