Question

Explain why the burning of a candle is an example of both physical as well as chemical changes.

Answer 1

The phenomena of candle burning involve both physical and chemical changes.

• When a candle is lit, the oxygen in the air reacts and carbon dioxide is produced.
• CO₂ is generated as a new substance.
• So it's a chemical transformation.
• There is no new substance generated when the candle melts, and the molten wax may be solidified and converted into a candle again, making it a reversible transformation.
• This shift can thus be described as physical.
• Hence, it is both physical as well as chemical change.