Home
Class 10
PHYSICS
Assertion: After white washing the walls...

Assertion: After white washing the walls, a shiny white finish on walls is obtained after two to three days.
Reason: Calcium Oxide reacts with Carbon dioxide to form Calcium Hydrogen Carbonate which gives shiny white finish.

A

Both A and R are true, and R is correct explanation of the assertion.

B

Both A and R are true, but R is not the correct explanation of the assertion.

C

A is true, but R is false.

D

A is false, but R is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that after whitewashing the walls, a shiny white finish is obtained after two to three days. - This is true because when whitewashing is done, the calcium oxide (CaO) in the whitewash reacts with carbon dioxide (CO2) in the air over time, leading to the formation of calcium carbonate (CaCO3), which is known for its shiny appearance. 2. **Understanding the Reason**: - The reason given is that calcium oxide reacts with carbon dioxide to form calcium hydrogen carbonate, which gives a shiny white finish. - This part is partially correct in that calcium oxide does react with carbon dioxide, but the product formed is calcium carbonate (CaCO3), not calcium hydrogen carbonate. Therefore, this statement is false. 3. **Conclusion**: - Since the assertion is true (shiny finish is obtained) and the reason is false (incorrect product formation), we conclude that the assertion is true and the reason is false. ### Final Answer: - The correct answer is that the assertion is true and the reason is false.
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that after whitewashing the walls, a shiny white finish is obtained after two to three days. - This is true because when whitewashing is done, the calcium oxide (CaO) in the whitewash reacts with carbon dioxide (CO2) in the air over time, leading to the formation of calcium carbonate (CaCO3), which is known for its shiny appearance. ...
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • SAMPLE QUESTION PAPER 2020-21 (SCIENCE)

    CBSE MODEL PAPER|Exercise SECTION B|9 Videos

  • SAMPLE QUESTION PAPER 2020-21 (SCIENCE)

    CBSE MODEL PAPER|Exercise SECTION C|7 Videos

  • SAMPLE PAPER 2024

    CBSE MODEL PAPER|Exercise P|11 Videos

Similar Questions

Explore conceptually related problems

Assertion (A) : Permanent hardness of water is removed by treatment with washing soda. Reason (R): Washing soda reacts with soluble magnesium and calcium sulphate to form insoluble carbonates.

(a) What are the various ways in which a chemical equation can be made more informative ? Give examples to illustrate your answer. (b) Write balanced chemical equation from the following information : An aqueous calcium hydroxide solution (lime water) reacts with carbon dioxide gas to produce a solid calcium carbonate precipitate and water.

Knowledge Check

  • Assertion (A) : After white washing the walls, a shiny white finish on walls is obtained after two to three days. Reason (R ) : Calcium Oxide reacts with Carbon dioxide to form Calcium Hydrogen Carbonate which gives shiny white finish.

    A
    Both A and R are true and R is the correct explanation of A.
    B
    Both A and R are true but R is NOT the correct explanation of A.
    C
    A is true but R is false.
    D
    A is false and R is True.

  • Assertion . Calcium and magnesium oxides are not reduced by carbon . Reason . Calcium and magnesium oxides react with carbon to form their respective carbides .

    A
    If both assertion and reason are true, and reason is the true explanation of the assertion.
    B
    If both assertion and reason are true, but reason is not the true explanation of the assertion.
    C
    If assertion is true, but reason is false
    D
    If both assertion and reason are false.

  • Assertion (A): Calcium and magnesium oxides are not reduced by carbon. Reason (R ): Calcium and magnesium oxides react with carbon to form their respected carbides.

    A
    If both `(A)` and `(R )` are correct and `(R )` is the correct explanation of `(A)`.
    B
    If both `(A)` and `(R )` are correct, but `(R )` is not the correct explanation of `(A)`.
    C
    If `(A)` is correct, but `(R )` is incorrect.
    D
    If `(A)` is incrrect, but `(R )` is correct.

    • Similar Questions

    Explore conceptually related problems

    While white washing Ca(OH)_(2) reacts slowly with CO_(2) in air to form a thin layer of ____on the walls.

    Assertion. Al is obtained by high temperature reduction of alumina with carbon. Reason. Alumina reacts with carbon to form aluminium carbide which decomposes at high temperature to from Al while carbon is oxidised to CO.

    Assertion: A1 is obtained by high temperature reduction of alumina with carbon. Reason: Alumina reacts with carbon to form A1_(2)O_(3) which does not decompose.

    Assertion: Permanent hardness of water can be removed by treatement with washing soda. Reason: Washing soda reacts with calcium and magnesium sulphates and chlorides to form insoluble carbonates.

    Assertion : All alkali metals do not form superoxides as one of the main products in excess of air on heating. Reason : Superoxide reacts with carbon monoxide producing a white powder and liberating dioxygen.

    Home
    Profile