Question

4. A potato remains a potato even after it is cooked so it should be physical change. Do you agree? Give example.

Answer 1

• When a potato is cooked, there is a change in the composition as well as the taste of the potato also changes.
• We cannot get back the raw potato from the cooked potato.
• Thus cooking of potatoes is a chemical change, not a physical change.
• Another example of chemical change is rusting of iron $\left(\mathrm{Fe}\right)$. Iron when exposed to air, reacts with oxygen and moisture present in the air and a reddish-brown coating of hydrated Iron oxide is formed. So, we cannot get back initial iron from hydrated Iron oxide.