PYQ Vault

Day 137: CBSE Class 10 Science

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

  1. Question 1

    Carbon and its Compounds. Asked once: 2024 (same type asked 2 times)

    34 (A)
    (i) Define the term functional group. Identify the functional groups present in the following carbon compounds : (I) CH3COCH3\mathrm{CH_3COCH_3} (II) CH3CH2COOH\mathrm{CH_3CH_2COOH} (ii) What happens when ethanol reacts with acidified potassium dichromate solution ? Write chemical equation for the reaction. Why is this reaction considered an oxidation reaction ? (iii) Write chemical equation for the reaction of ethanoic acid with sodium hydroxide.

  2. Question 2

    Carbon and its Compounds. Asked once: 2025 (same type asked 2 times)

    34 (a)
    (i) Draw two isomeric structures of Butene (C4H8)(\mathrm{C_4H_8}). (ii) Name the following compounds : (I) CH3−CH2−CH2−Cl\mathrm{CH_3{-}CH_2{-}CH_2{-}Cl} (II) CH3−CH2−CO−CH3\mathrm{CH_3{-}CH_2{-}CO{-}CH_3} (iii) Write the chemical equations for the following reactions. Mention one essential condition each for these reactions to take place. (I) Ethanol undergoes complete oxidation (II) Propene undergoes hydrogenation (III) Ethanoic acid reacts with ethanol

  3. Question 3

    Chemical Reactions and Equations. Asked once: 2026 (same type asked 2 times)

    26
    What happens when (i) potassium iodide solution is added to lead (II) nitrate solution ? (ii) zinc is added to copper (II) chloride solution ? (iii) hydrogen gas is passed over hot copper (II) oxide ? Write balanced chemical equations of the reactions involved in support of your answer.

  4. Question 4

    Control and Coordination. Asked once: 2025 (same type asked 2 times)

    The growth movements of plant parts in which the direction of the stimulus determines the direction of the response is known as tropic movements or tropism. Plants also have non-directional movements which may not be growth dependent.
    38 (I)
    Name the movement which causes ‘X’ and ‘Y’ to grow downwards and upwards respectively.

  5. Question 5

    Control and Coordination. Asked once: 2024 (same type asked 2 times)

    29
    Taking the example of any two animal hormones along with their gland of secretion, explain how these hormones help (i) in growth and development and (ii) regulate metabolism, in the body.