When a candle burns, both physical and chemical changes take place. Identify these changes. Give another example of a familiar process in which both the chemical and physical changes take place.

When a candle burns, both physical and chemical changes occur:
  • Physical change: melting of wax, vapourisation of melted wax.
  • Chemical change: Burning of vapours of wax to give carbon dioxide, heat and light.
LPG is another example in which physical change occurs when LPG comes out of the cylinder and is converted from liquid to gaseous state and a chemical change occurs when gas burns in air.

[Explanation: The burning of a candle is both physical and chemical change as:
Physical changes: While burning the candle the wax slowly melts as the candle gets smaller and this molten wax can be again solidified and will make it into a candle which means that it is a reversible change.
Chemical changes: The heat produced by the candle consumes both the oxygen in the atmosphere, as well as the fuels coming from the flame. This will then lead to carbon dioxide emissions produced by the flame. This is an irreversible change.]


Simply Easy Learning

Updated on: 10-Oct-2022


Kickstart Your Career

Get certified by completing the course

Get Started