PYQ Vault
EbooksTutor

Find the coefficients that balance an equation

This type of question, asked 4 times: 2023, 2024, 2025, 2026. All 7 questions below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    2023

    3
    MnO2+x HCl→MnCl2+y H2O+z Cl2\mathrm{MnO_2} + x\,\mathrm{HCl} \rightarrow \mathrm{MnCl_2} + \mathrm{y\,H_2O} + \mathrm{z\,Cl_2} In order to balance the above chemical equation, the values of xx, y and z respectively are :

    Tap an option to check your answer.

  2. Question 2

    2023

    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

    2024

    5
    Consider the following Chemical equation : a Al2O3\mathrm{Al_2O_3} + b HCl\mathrm{HCl} ⟶\longrightarrow c AlCl3\mathrm{AlCl_3} + d H2O\mathrm{H_2O} In order to balance this chemical equation, the values of a, b, c and d must be

    Tap an option to check your answer.

  4. Question 4

    2025

    1
    Consider the following chemical equation : p Al+q H2O⟶r Al2O3+s H2\mathrm{p\,Al + q\,H_2O \longrightarrow r\,Al_2O_3 + s\,H_2} To balance this chemical equation, the values of ‘p’, ‘q’, ‘r’ and ‘s’ must be respectively :

    Tap an option to check your answer.

  5. Question 5

    2025

    27 (A)
    Why do we balance a chemical equation? Name and state the law that suggests the balancing of a chemical equation? Balance the following chemical equation : Zn+H3PO4→Zn3(PO4)2+H2\mathrm{Zn + H_3PO_4 \rightarrow Zn_3(PO_4)_2 + H_2}

  6. Question 6

    2025

    21
    Balance the following chemical equations : (a) CO2+H2O→ChlorophyllSunlightC6H12O6+O2+H2O\mathrm{CO_2 + H_2O \xrightarrow[\text{Chlorophyll}]{\text{Sunlight}} C_6H_{12}O_6 + O_2 + H_2O} (b) Pb(NO3)2→HeatPbO+NO2+O2\mathrm{Pb(NO_3)_2 \xrightarrow{\text{Heat}} PbO + NO_2 + O_2}

  7. Question 7

    2026

    19
    In the following equation x KI+H2O2⟶I2+y KOH\mathrm{x\,KI + H_2O_2 \longrightarrow I_2 + y\,KOH} x and y respectively are :

    Tap an option to check your answer.