PYQ Vault
EbooksTutor

Temperature at which delta G = 0 (change over between spontaneous and non-spontaneous)

The same question, asked 6 times: 14 May 2024 S2*, 25 Apr 2025 S2*, 13 Apr 2026 S1*, 15 Apr 2026 S2*, 18 Apr 2026 S1*, 12 May 2026 S1. Every wording below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    14 May 2024 S2

    94
    For a reaction A + B →\rightarrow products ΔH=−84.2 kJ\Delta H = -84.2\,\text{kJ} and ΔS=−200 J K−1\Delta S = -200\,\text{J K}^{-1}. Calculate the highest value of temperature for forward spontaneity.

    Tap an option to check your answer.

  2. Question 2

    25 Apr 2025 S2

    97
    For a certain reaction, ΔH=−210 kJ\Delta H = - 210\text{ }kJ and ΔS=−150 kJ K−1\Delta S = - 150\text{ }kJ{\text{ }K}^{- 1} Find the temperature so that ΔG=0\Delta G = 0.

    Tap an option to check your answer.

  3. Question 3

    13 Apr 2026 S1

    7
    For a certain reaction ΔH=−50\Delta H = -50 kJ and ΔS=−100\Delta S = -100 J/K find the temperature so that the reaction is spontaneous.

    Tap an option to check your answer.

  4. Question 4

    15 Apr 2026 S2

    7
    For a certain reaction, ΔH0\Delta H^0 is −345-345 kJ and ΔS0\Delta S^0 is −123 JK−1-123\ \mathrm{JK^{-1}}. At what temperature the change over from spontaneous to nonspontaneous will occur?

    Tap an option to check your answer.

  5. Question 5

    18 Apr 2026 S1

    8
    For a certain reaction, ΔH∘=40\Delta\mathrm{H}^\circ = 40 kJ and ΔS∘=80 JK−1\Delta\mathrm{S}^\circ = 80\ \mathrm{JK^{-1}}. Find the temperature so that ΔG∘=0\Delta\mathrm{G}^\circ = 0

    Tap an option to check your answer.

  6. Question 6

    12 May 2026 S1

    6
    For a certain reaction, change in enthalpy is −225-225 kJ and entropy change =−150 JK−1= -150\ \mathrm{JK^{-1}}. Find the temperature so that ΔG\Delta G is zero.

    Tap an option to check your answer.