Advertisements
Advertisements
Question
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.
Solution
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
RELATED QUESTIONS
Dead burnt plaster is ______.
Suspension of slaked lime in water is known as ______.
A substance which gives brick red flame and breaks down on heating to give oxygen and a brown gas is ______.
Dehydration of hydrates of halides of calcium, barium and strontium i.e., CaCl26H2O, BaCl2.2H2O, SrCl2.2H2O, can be achieved by heating. These become wet on keeping in air. Which of the following statements is correct about these halides?
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 |
Initial setting of cement is mainly due to ______.
\[\ce{Y <-[\Delta, 205°C] CaSO4.2H2O ->[\Delta, 120°C] X}\]
X and Y are respectively:
The commercial name for calcium oxide is ______.
Which of the following on thermal decomposition yields a basic as well as acidic oxide?
The substance not likely to contain CaCO3 is ______.
