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Question

Solid calcium oxide was take in a container and water was added slowly to it, (i) State the two observations made in the experiment. (ii) Write the name and chemical formula of the product formed.

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Answer

(i) Following are the two observation:

(a) Calcium oxide (CaO) reacts vigorously with water to form slaked lime.

(b) The container becomes hot because a large amount of heat is released during this reaction.

(ii) The product formed is slaked lime for lime for which the chemical formula is Ca(OH)2.

CaO + H2​O → Ca(OH)2 ​+ heat

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