Advertisements
Advertisements
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
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.
APPEARS IN
संबंधित प्रश्न
Find the oxidation state of sodium in Na2O2.
Describe two important uses of the following sodium carbonate.
What happens when sodium metal is dropped in water?
State as to why a solution of Na2CO3 is alkaline?
Write a balanced equation for the reaction between Na2O2 and water.
When Zeolite, which is hydrated sodium aluminium silicate is treated with hard water, the sodium ions are exchanged with which of the following ion(s)?
(i) H+ ions
(ii) Mg2+ ions
(iii) Ca2+ ions
(iv) \[\ce{SO^{2-}4}\] ions
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 |
\[\ce{NaOH}\] is manufactured by the electrolysis of brine solution. The products of the reaction are ______.
