Exercise Questionsncert Solutions for Class 6 Science Chapter 6
1. To walk through a waterlogged area, you usually shorten the length of your dress by folding it. Can this change be reversed?
Solution:
Yes, the process can be reversed.
2. You accidentally dropped your favorite toy and broke it. This is a change you did not want. Can this change be reversed?
Solution:
No, this change cannot be reversed
3. Some changes are listed in the following table. For each change, write in the blank column, whether the change can be reversed or not.
| Sl No | Change | Can be reversed Yes/No |
| 1 | The sawing of a piece of wood | |
| 2 | The melting of ice candy | |
| 3 | Dissolving sugar in water | |
| 4 | The cooking of food | |
| 5 | The ripening of a mango | |
| 6 | Souring of milk |
Solution :
| Sl No | Change | Can be reversed Yes/No |
| 1 | The sawing of a piece of wood | No |
| 2 | The melting of ice candy | Yes |
| 3 | Dissolving sugar in water | Yes |
| 4 | The cooking of food | No |
| 5 | The ripening of a mango | No |
| 6 | Souring of milk | No |
4. A drawing sheet changes when you draw a picture on it. Can you reverse this change?
Solution:
This change can be reversed if a pencil is used to draw the picture. If a pen, paint, oil /water colours are used to draw the picture, change cannot be reversed.
5. Give examples to explain the difference between changes that can or cannot be reversed.
Solution:
Changes that can be reversed
i) Opening and closing the door
ii) Filling glass with water
Changes that cannot be reversed
i) Conversion of milk into curd
ii) Ripening of fruit
6. A thick coating of a paste of Plaster of Paris (POP) is applied over the bandage on a fractured bone. It becomes hard on drying to keep the fractured bone immobilized. Can the change in POP be reversed?
Solution:
No, the change cannot be reversed
7. A bag of cement lying in the open gets wet due to rain during the night. The next day the sun shines brightly. Do you think the changes, which have occurred in the cement, could be reversed?
Solution: No, the change cannot be reversed
Important topics covered in ncert Solutions for Class 6 Science Chapter 6 Changes Around Us
- Can all changes always be reversed?
- Could there be other ways to bring a change?
- Some common changes
- Evaporation
- Expansion
- Contraction
- Melting