Question

Statement 1: Melting of candle wax is a physical change and the melted wax can again be obtained as solid wax upon the removal of heat.

Statement 2: Burning of candle wick is a chemical change and the wick cannot be obtained back in its original form.

Based on the given statements, choose the right option.

• A. Statement 1 is correct
• B. Statement 2 is correct
• C. Both 1 and 2 are correct
• D. Both 1 and 2 are incorrect

Answer 1

The correct option is C Both 1 and 2 are correct

Physical change affects the phase or form of the elements involved but not their chemical composition.
Melting involves only the change in the shape of wax and so it is a physical change.
Also, melting is a reversible process. The molten wax can be converted back to solid by freezing it.

Chemical change is the change of substances to other new substances with different chemical properties. This happens due to the change in their composition.
So, when a candle is burnt, the wick made of cotton burns and its composition changes. Thus, it is a chemical change.
Also, burning is an irreversible process. We cannot obtain the wick back in its original form once it is burnt.