How can you distinguish between a physical change and a chemical change?

Physical Change

When a substance undergoes a physical change, its composition remains the same despite its molecules being rearranged.Physical change is a temporary change.A Physical change affects only physical properties i.e. shape, size, etc.A physical change involves very little to no absorption of energy.Some examples of physical change are freezing of water, melting of wax, boiling of water, etc..In a physical change, no new substance is formed.Physical change is easily reversible i.e original substance can be recovered.

Chemical Change

When a substance undergoes a chemical change, its molecular composition is changed entirely. Thus, chemical changes involve the formation of new substances..A chemical change is a permanent change.Chemical change both physical and chemical properties of the substance including its compositionDuring a chemical reaction, absorption and evolution of energy take place.A few examples of chemical change are digestion of food, burning of coal, rusting, etc.A chemical change is always accompanied by one or more new substance(s).Chemical changes are irreversible i.e. original substance cannot be recovered.

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