Give two examples for each of the following cases:

(a) Physical changes which are reversible.


(b) Physical changes which are not reversible.


(c) Chemical changes.


(a) Examples of physical changes which are reversible:

i) Melting of wax.


ii) Formation of sugar crystals from its solution.


(b) Examples of physical changes which are not reversible:


i) Tearing of paper


ii) Cutting log of wood


(c) Examples of chemical changes:


i) Reaction between lime water and carbon dioxide


ii) Burning of magnesium ribbon


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