Predict which of the following changes can be reversed and which cannot be reversed Class 7

Predict which of the following changes can be reversed and which cannot be reversed Class 7

Predict which of the following changes can be reversed and which cannot be reversed. If you are not sure, you may write that down. Why are you not sure about these? Class 7

Answer:

1. Stitching cloth to a shirt Cannot be reversed: Once stitched, it is difficult to unstitch without damage.
2. Twisting of straight string-Can be reversed: The string can be untwisted easily.
3. Making idlis from a batter Cannot be reversed: The batter cannot be returned to its original form after steaming.
4. Dissolving sugar in water - Can be reversed: Sugar can be recovered by evaporating water.
5. Drawing water from a well-Can be reversed: Water can be returned to the well.
6. Ripening of fruits - Cannot be reversed: Once ripe, fruits cannot go back to unripe.
7. Boiling water in an open pan Can be reversed: Evaporated water can be obtained back by condensation.
8. Rolling up a mat - Can be reversed: The mat can be unrolled.
9. Grinding wheat grains to flour Cannot be reversed: Flour cannot be turned back into grains.
10. Forming of soil from rocks - Cannot be reversed: Soil formation is a slow process and cannot form rock back.