On heating calcium carbonate gets converted into calcium oxide and carbon dioxide.

(a) Is this a physical or a chemical change?


(b) Can you prepare one acidic and one basic solution by using the products formed in the above process? If so, write the chemical equation involved.

(a) Heating of calcium carbonate to get calcium oxide and carbon dioxide is a chemical change as new substance with different composition and chemical properties are formed.

CaCO3 (Calcium carbonate) CaO (Calcium oxide) + CO2 (Carbon dioxide)
(b) Acidic and basic solutions can be prepared by dissolving the products of the above process in water.


When CaO dissolves in water it forms calcium hydroxide which is basic solution.


CaO+H2O Ca(OH)2 (basic solution)


When CO2(g) dissolves in water it forms carbonic acid which is an acidic solution.


CO2 + H2OH2CO3 (acidic solution)


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