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प्रश्न
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.
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उत्तर
(a) It is a chemical change in which new substances are formed.
(b) Calcium oxide when dissolved in water, forms a basic solution.
\[\ce{CaO + H2O -> (OH)2}\]
Carbon dioxide when dissolved in water, forms an acidic solution
\[\ce{CO2 + H2O -> H2CO3}\]
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संबंधित प्रश्न
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\[\ce{NH3_{(g)} + HCl_{(g)} -> NH4Cl_{(s)}}\]
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- Colour change
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A coloured substance which leaves on strong heating a black residue and evolves two colourless gases one of which is acidic and the other neutral.
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2Mg + O2 → 2Mg O
