Advertisements
Advertisements
प्रश्न
When water is added to compound (A) of calcium, solution of compound (B) is formed. When carbon dioxide is passed into the solution, it turns milky due to the formation of compound (C). If excess of carbon dioxide is passed into the solution milkiness disappears due to the formation of compound (D). Identify the compounds A, B, C and D. Explain why the milkiness disappears in the last step.
उत्तर
Compound A reacts with water to form compound B. So, the compound A is calcium oxide. When water is added to calcium oxide, calcium hydroxide is formed. It is lime water. The compound gives a milky appearance which is compound C. The compound C is calcium carbonate. On passing, excess carbon dioxide milkiness disappears due to the formation of compound D. The compound is calcium hydrogen carbonate. The reactions are as follows:
\[\ce{CaO + H2O -> Ca(OH)2}\]
\[\ce{Ca(OH)2 + CO2 -> CaCO3}\]
\[\ce{Ca(OH)2 + CO2 + H2O -> Ca(HCO3)2}\]
APPEARS IN
संबंधित प्रश्न
Describe two important uses of the following quicklime.
Describe the importance of the limestone.
Describe the importance of the cement.
Describe the importance of the plaster of paris.
A substance which gives brick red flame and breaks down on heating to give oxygen and a brown gas is ______.
Several sodium compounds find use in industries. Which of the following compounds are used for textile industry?
(i) Na2CO3
(ii) NaHCO3
(iii) NaOH
(iv) NaCl
Match the elements given in Column I with the properties mentioned in Column II.
| Column I | Column II |
| (i) Li | (a) Insoluble sulphate |
| (ii) Na | (b) Strongest monoacidic base |
| (iii) Ca | (c) Most negative EΘ value among alkali metals. |
| (iv) Ba | (d) Insoluble oxalate |
| (e) 6s2 outer electronic configuration |
The conversion of hydroxyapatite occurs due to presence of p - ions in water. The correct formula of hydroxyapatite is ______.
The commercial name for calcium oxide is ______.
In curing cement plasters, water is sprinkled from time to time. This helps in ______.
