Chemical A is used for water softening to remove temporary hardness, A reacts with Na2Co3 to generate caustic soda. When CO2 is bubbled through A, it turns cloudy. If the chemical formula of A is \(Ca (OH)_{2} + CO_{2} \rightarrow CaCo_{?} \downarrow + H_{2}O \) then what is the value of ?
Chemical A is used for water softening to remove temporary hardness, A reacts with Na2Co3 to generate caustic soda. When CO2 is bubbled through A, it turns cloudy. If the chemical formula of A is \(Ca (OH)_{2} + CO_{2} \rightarrow CaCo_{?} \downarrow + H_{2}O \) then what is the value of ?
Correct Answer: 3
Solution and Explanation
The chemical is calcium hydroxide It is used for water softening to remove temporary hardness. It reacts with sodium carbonate to form caustic soda.With carbon dioxide gas, it forms calcium carbonate which turns lime water milky. Hence, the correct answer is 3.
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