PYQ Vault

Day 26: CBSE Class 10 Science

5 questions. Try each one first, then open its answer.

  1. Question 1

    Acids, Bases and Salts. Asked 2 times: 2023*, 2025 (* = numbers or wording changed that year)

    2
    The formula of washing soda is

    Tap an option to check your answer.

  2. Question 2

    Carbon and its Compounds. Asked 2 times: 2023*, 2025 (* = numbers or wording changed that year)

    35 (a)
    A saturated organic compound ‘A’ with two carbon atoms belongs to the homologous series of alcohols. On oxidation, it forms an organic acid ‘B’ with molecular mass 60 u. On heating ‘A’ with excess concentrated sulphuric acid at 443 K, an unsaturated hydrocarbon ‘C’ is formed. (i) Name A, B and C. (ii) Calculate molecular mass of C. (iii) What happens when a pinch of sodium carbonate is added to compound B ? Write chemical equation for the reaction. (iv) Draw electron dot structure of compound B.

  3. Question 3

    Carbon and its Compounds. Asked 2 times: 2024*, 2025 (* = numbers or wording changed that year)

    34 (b)
    (a) Write the molecular formula of ethyne and draw its electron dot structure. (b) Write chemical equation to show the reaction of ethanol with (i) Sodium metal (ii) Ethanoic acid (in the presence of an acid) (iii) Acidified potassium dichromate Write the name of the product formed in each case.

  4. Question 4

    Carbon and its Compounds. Asked 2 times: 2024*, 2025 (* = numbers or wording changed that year)

    4
    A Hydrocarbon which does not belong to the same homologous series of carbon compounds is

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  5. Question 5

    Carbon and its Compounds. Asked 2 times: 2024*, 2025 (* = numbers or wording changed that year)

    22
    What are micelles ? Draw the structure.