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प्रश्न
A chemical A is used for the preparation of washing soda to recover ammonia. When CO2 is bubbled through an aqueous solution of A, the solution turns milky. It is used in whitewashing due to disinfectant nature. What is the chemical formula of A?
विकल्प
Ca(HCO3)2
CaO
Ca(OH)2
CaCO3
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उत्तर
Ca(OH)2
Explanation:
The chemical formula of A is Ca(OH)2. Sodium carbonate is prepared by Solvay's process. In this process, ammonia is recovered when ammonium chloride reacts with calcium hydroxide. On reacting NH4Cl with Ca(OH)2, calcium chloride is obtained as a by-product. The reaction is given below.
\[\ce{2NH4Cl + Ca(OH)2 -> 2NH3 + CaCl2 + H2O}\]
When CO2 is bubbled through an aqueous solution of Ca(OH)2 the solution turns milky. It is used in whitewashing due to its disinfectant nature.
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संबंधित प्रश्न
Find the oxidation state of sodium in Na2O2.
Discuss the various reactions that occur in the Solvay process.
Describe two important uses of each of the following caustic soda.
Describe two important uses of the following sodium carbonate.
What happens when sodium metal is dropped in water?
What happens when sodium metal is heated in the free supply of air?
Write a balanced equation for the reaction between Na2O2 and water.
Amphoteric hydroxides react with both alkalies and acids. Which of the following Group 2 metal hydroxides is soluble in sodium hydroxide?
Complete the following reactions.
\[\ce{O^{-}2 + H2O ->}\]
In the Solvay process, can we obtain sodium carbonate directly by treating the solution containing (NH4)2CO3 with sodium chloride? Explain.
Match the compounds given in Column I with their uses mentioned in Column II.
| Column I | Column II |
| (i) CaCO3 | (a) Dentistry, ornamental work |
| (ii) Ca(OH)2 | (b) Manufacture of sodium carbonate from caustic soda |
| (iii) CaO | (c) Most negative E value among alkali O metals. |
| (iv) CaSO4 | (c) Manufacture of high-quality paper |
| (d) Used in white washing |
Match the elements given in Column I with the colour they impart to the flame given in Column II.
| Column I | Column II |
| (i) Cs | (a) Apple green |
| (ii) Na | (b) Violet |
| (iii) K | (c) Brick red |
| (iv) Ca | (d) Yellow |
| (v) Sr | (e) Crimson red |
| vi) Ba | (f) Blue |
Amongst baking soda, caustic soda and washing soda, carbonate anion is present in ______.
The pair of compounds which cannot exist together in solution is ______.
Which sodium salt will be heated with soda lime to obtain propane?
