Question

Why is it that burning of a candle involves both physical and chemical changes?

Answer 1

the Burning of a candle involves physical and chemical changes given below:

• Melting of wax: When a candle is burnt, melting of wax takes place. This is a physical process as there is no formation of a new chemical substance. It involves only a change in the state of the wax from solid to liquid form.
• Burning of the wick of candle: Melting of wax is accompanied by burning of the wick of the candle which is a chemical change as the wick is burnt to release Carbon dioxide $\left({\mathrm{CO}}_2\right)$ , light, and heat.

Physical and chemical change is defined as follows:

• Physical change: A physical change involves the formation of no new substance and there is no change in the chemical composition of the substance undergoing the change.
• Chemical change: A chemical change involves the formation of one or more new substances and there is a change in the chemical composition of the substance undergoing the change.