Advertisements
Advertisements
Question
Write the method of preparation of Ca(OH)2. What happens when CO2 is passed through it? Write balanced chemical equation for the reaction involved.
Advertisements
Solution
- The method of preparation of calcium hydroxide Ca(OH)2 involves adding water to calcium oxide (quick lime). When water is slowly added to calcium oxide, it reacts vigorously to produce slaked lime (calcium hydroxide), releasing a significant amount of heat in the process. The chemical equation for this reaction is:
\[\ce{CaO(s) + H2O(l) -> Ca(OH)2(aq) + Heat}\] - When carbon dioxide CO2 is passed through a solution of calcium hydroxide, it reacts to form calcium carbonate CaCO3 and water. This reaction is depicted by the equation:
\[\ce{Ca(OH)2(aq) + CO2(g)->CaCO3(s) + H2O(l)}\] - If an excess of carbon dioxide is passed through the mixture, it further reacts with the calcium carbonate to form calcium bicarbonate, which is soluble in water:
\[\ce{CaCO3(s) + H2O(l) + CO2(g) -> Ca(HCO3)2(aq)}\] - This sequence of reactions begins with a combination reaction to form calcium hydroxide, followed by a double displacement reaction upon the introduction of carbon dioxide, first leading to the precipitation of calcium carbonate and then, upon the introduction of more carbon dioxide, forming the soluble calcium bicarbonate. The compound that precipitates in the initial reaction with CO2 is calcium carbonate CaCO3 , and the ions present in it are Ca2+ and `"CO"_3^(2-).`
APPEARS IN
RELATED QUESTIONS
Write the balanced chemical equation for the following and identify the type of reaction.
\[\ce{Potassium bromide (aq) + Barium iodide (aq) -> Potassium iodide (aq) + Barium bromide (s)}\]
What happens when silver nitrate solution is added to sodium chloride solution?
Name the type of reaction involved.
- What happens when an aqueous solution of sodium sulphate reacts with an aqueous solution of barium chloride?
- Write the balanced chemical equation for the reaction which takes place.
- State the physical conditions of reactants in which the reaction will not take place.
- Name the type of chemical reaction which occurs.
- Give one example of another reaction which is of the same type as the above reaction.
A red-brown metal X forms a salt XSO4. When hydrogen sulphide gas is passed through an aqueous solution of XSO4, then a black precipitate of XS is formed alongwith sulphuric acid solution.
- What could the salt XSO4 be?
- What is the colour of salt XSO4?
- Name the black precipitate XS.
- By using the formula of the salt obtained in (a) above, write an equation of the reaction which takes place when hydrogen sulphide gas is passed through its aqueous solution.
- What type of chemical reaction takes place in this case?
Study the following chemical reaction and answer the questions given below:
\[\ce{AgNO3_{(aq)} + NaCl_{(aq)} -> \underset{(Precipitate)}{AgCl_{(s)}}↓ + NaNO3_{(aq)}}\]
- Identify and write the type of chemical reaction.
- Write the definition of the above type of chemical reaction.
- Write the names of the reactants and products of the above reaction.
Classify the following reaction into –
- Direct combination
- Decomposition
- Displacement
- Double decomposition
The reaction is – Zinc sulphate reacts with ammonium hydroxide to give ammonium sulphate and zinc hydroxide.
Which option denotes a double displacement reaction?
In a double displacement reaction ______.
Write balanced chemical equation for the following word equation.
Lead nitrate + Potassium iodide → Lead iodide + Potassium nitrate
Is this a double displacement reaction? Justify your answer. Name the compound precipitated and write the ions present in it.
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
