PYQ Vault
EbooksTutor

Enthalpy per mole from a given thermochemical equation

This type of question, asked 3 times: May 2022 S1, 9 May 2023 S2, 21 Apr 2025 S1. All 3 questions below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    May 2022 S1

    85
    What is the heat of formation of HCl(g) from following equation? H2(g)+Cl2(g)→2HCl(g)\text{H}_2(\text{g}) + \text{Cl}_2(\text{g}) \rightarrow 2\text{HCl(g)}, ΔfH=−194\Delta_f H = -194 kJ

    Tap an option to check your answer.

  2. Question 2

    9 May 2023 S2

    99
    For the reaction, 2H2_2(g) + O2_2(g) →\rightarrow 2H2_2O(g), ΔH∘=−573.2\Delta H^\circ = -573.2 kJ. What is heat of decomposition of water per mol?

    Tap an option to check your answer.

  3. Question 3

    21 Apr 2025 S1

    79
    Find standard enthalpy of formation of ammonia from following reaction.
    N2( g)+3H2( g)⟶2NH3( g);ΔrH0=−92.0 kJN_{2(\text{ }g)}+ 3H_{2(\text{ }g)}\longrightarrow 2NH_{3(\text{ }g)};\Delta_{r}H^{0}= - 92.0\text{ }kJ

    Tap an option to check your answer.