Question

A potter working on his wheel, shaped a lump of clay into a pot. He then baked the pot in an oven. Do these two acts lead to the same kind of changes or different? Give your opinion and justify your answer.

Answer 1

The shaping of clay into a pot is can be categorised as a physical change whereas baking the pot in an oven is a chemical change.

Physical changes: During a physical change, no new chemical substance is formed with different chemical properties.

• It can be reversed and is a temporary change. Examples: Melting of wax, freezing of ice etc.
• As the pot converted from clay can be reconverted into clay and given a different shape, it is a physical change.

Chemical changes: The change in which the molecular composition is completely altered and a new product is formed is called a chemical change.

• A chemical change is irreversible or is a permanent change. Examples: Burning of a piece of paper, cooking of the raw egg etc.
• Once baked into a pot, it cannot be changed into any other shape and this change is permanent. So baking of pot in an oven is a chemical change.