Illustrate with an example that physical and chemical changes can take place together ?
When the candle burns,both physical and chemical changes occur:
Candle is made up of a solid block of wax with a wick embedded in it.
1) Physical Change
When candle is lit, the heat of the flame melts the solid wax to liquid wax. This signifies a physical change from solid state to liquid state.
2) Chemical Change
The wax acts as a fuel when we light the candle and is basically a chemical substance called carbon. The carbon combines with oxygen to form another chemical substance called carbon dioxide. Also the unburnt carbon is deposited as black substance called soot. This signifies a chemical change.