MELTING OF WAX IS PHYSICAL CHANGE GIVE EXAMPLE OF CHEMICAL CHANGE SIMILAR TO THAT OR ANY OTHER
The correct answer and explanation is:
Correct Answer:
Melting of wax is a physical change. A similar chemical change example would be burning of wax.
Explanation (300 words):
Melting of wax is considered a physical change because it involves a change in the state of matter—from solid to liquid—without altering the chemical composition of the wax. The molecules remain the same; only their physical arrangement and energy change due to heating. When the wax cools, it can solidify back to its original state, indicating the process is reversible.
In contrast, a chemical change results in the formation of new substances with different chemical properties. A good example of a chemical change involving wax is its burning. When wax burns, it reacts with oxygen in the air in a process called combustion. The hydrocarbons in the wax combine with oxygen to form new substances—mainly carbon dioxide (CO₂) and water vapor (H₂O). This process is irreversible under normal conditions and involves the breaking and forming of chemical bonds, which is a key feature of chemical changes.
Unlike melting, burning also releases light and heat energy, which further confirms that a chemical reaction has taken place. You cannot retrieve the original wax from the gases and ash produced by burning, while in melting, the wax can return to its original form upon cooling.
Another example of a chemical change, though not directly related to wax, is rusting of iron. In this reaction, iron reacts with oxygen and moisture from the environment to form iron oxide, a new substance. Like burning wax, rusting cannot be reversed simply by physical means.
To summarize, melting of wax is a reversible physical change involving no new substance, while burning of wax is a chemical change that forms new compounds and cannot be reversed. These differences help us classify changes in matter correctly based on observable properties and chemical behavior.