Question

compound ''A'' when dissolved in water give compound ''B'' which is used in white-washing. ''B'' reacts with CO2 to form a white precipitate of compound ''C'' . Identify the compound ''A'' , ''B'' , ''C'' . Also write the equation involved.


anyone please answer it urgently......

Answer 1

Compound A reacts with water to form a compound B that is used in white-washing.

Since Ca(OH)₂ is used in white washing,

• Compound A + H₂O (l) → Ca(OH)₂ (aq)

Hence Compound A can be CaO called “Quick Lime”.

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Now, Compound B reacts with CO₂ to have compound C which is white precipitate.

• Ca(OH)₂ + CO₂ → CaCO₃ + H₂O

We also know that CaCO₃ is a white precipitate, hence Compound C is CaCO₃

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Compound A : CaO

Compound B : Ca(OH)₂

Compound C : CaCO₃

Answer 2

$\Large{\mathfrak{\underline{\underline{Solution :-}}}}$

$\sf A + water \longrightarrow B \\ \sf B + CO_2 \to C$

We know that Slaked lime with chemical formula $\bf \mathsf{Ca}(\mathsf{OH})_{2}$ is used for whitewashing which can be prepared by the reaction of quicklime that is CaO with water. Hence A is CaO and B is $\bold{\mathsf{Ca}(\mathsf{OH)}_{2}}$ here.

$\mathsf{CaO}+\mathsf{H}_{2} \mathsf{O} \rightarrow \mathsf{Ca}(\mathsf{OH})_{2}$

$\mathsf{Ca}(\mathsf{OH})_{2}+\mathsf{CO}_{2} \rightarrow \mathsf{CaCO}_{3}(\mathsf{C})+\mathsf{H}_{2} \mathsf{O}$

And $\mathsf{CaCO}_{3}$ is the white precipitate which is formed by the reaction of slaked lime and carbon dioxide.