PYQ Vault

Day 204: CBSE Class 10 Science

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

  1. Question 1

    Chemical Reactions and Equations. Asked once: 2023 (same type asked 4 times)

    27
    (a) Define a double displacement reaction. (b) Write the chemical equation of a double displacement reaction which is also a (i) Neutralization reaction and (ii) Precipitation reaction. Give justification for your answer.

  2. Question 2

    Chemical Reactions and Equations. Asked once: 2023 (same type asked 4 times)

    1
    To balance the following chemical equation the values of xx and y should respectively be : 2NaOH+x Al2O3⟶y NaAlO2+H2O\mathrm{2NaOH} + x\,\mathrm{Al_2O_3} \longrightarrow \mathrm{y}\,\mathrm{NaAlO_2 + H_2O}

    Tap an option to check your answer.

  3. Question 3

    Chemical Reactions and Equations. Asked once: 2023 (same type asked 4 times)

    27
    (a) Define oxidation. (b) Identify the oxidising agent in the following reactions and balance the chemical equations : (i) Pb3O4+HCl⟶PbCl2+Cl2+H2O\mathrm{Pb_3O_4 + HCl \longrightarrow PbCl_2 + Cl_2 + H_2O} (ii) MnO2+Al⟶Mn+Al2O3\mathrm{MnO_2 + Al \longrightarrow Mn + Al_2O_3}

  4. Question 4

    Control and Coordination. Asked once: 2025 (same type asked 4 times)

    23
    A person is making a list to purchase few things from a nearby market. Explain how the fore-brain plays an important role in performing this activity.

  5. Question 5

    Electricity. Asked once: 2022 (same type asked 4 times)

    11
    (a) State Ohm’s Law. Represent it mathematically. (b) Define 1 ohm. (c) What is the resistance of a conductor through which a current of 0.5 A flows when a potential difference of 2 V is applied across its ends ?