Gibbs Free Energy
For a reaction to be spontaneous at all temperatures, which condition must be satisfied?
Select the correct option:
🔒 Solution Hidden from View
Submit your answer to unlock the detailed step-by-step solution.
More chemical thermodynamics Practice Questions
At 298 K, a reaction has ΔH = +25 kJ mol⁻¹ and ΔS = +120 J mol⁻¹ K⁻¹. Is the reaction spontaneous at...
At 298 K, a reaction has ΔH = +25 kJ mol⁻¹ and ΔS = +120 J mol⁻¹ K⁻¹. Is the reaction spontaneous at...
The relationship between Gibbs free energy change and cell potential is:
The relationship between Gibbs free energy change and cell potential is:
According to the Third Law of Thermodynamics, the absolute entropy of a perfect crystalline substanc...
According to the Third Law of Thermodynamics, the absolute entropy of a perfect crystalline substanc...
A Carnot engine operates between a hot reservoir at 600 K and a cold reservoir at 300 K. If it absor...
A Carnot engine operates between a hot reservoir at 600 K and a cold reservoir at 300 K. If it absor...
The reduction of iron(III) oxide by carbon monoxide proceeds via the overall reaction (Fe_2O_3(s) +...
The reduction of iron(III) oxide by carbon monoxide proceeds via the overall reaction (Fe_2O_3(s) +...
The standard enthalpy of formation of liquid water is -285.8 kJ/mol and of water vapour is -241.8 kJ...
The standard enthalpy of formation of liquid water is -285.8 kJ/mol and of water vapour is -241.8 kJ...
For an ideal gas undergoing a reversible adiabatic expansion, starting at (T_1 = 400) K and (V_1 ...
For an ideal gas undergoing a reversible adiabatic expansion, starting at (T_1 = 400) K and (V_1 ...
Using the Born-Haber cycle for the formation of MgCl(_2)(s), given the following data — sublimatio...
Using the Born-Haber cycle for the formation of MgCl(_2)(s), given the following data — sublimatio...
An ideal gas undergoes reversible adiabatic compression. Which of the following correctly describes ...
An ideal gas undergoes reversible adiabatic compression. Which of the following correctly describes ...
The enthalpy of vaporisation of benzene is 30.8 kJ/mol at its boiling point of 353 K. What is the en...
The enthalpy of vaporisation of benzene is 30.8 kJ/mol at its boiling point of 353 K. What is the en...
At constant pressure, the molar heat capacity of nitrogen gas ((C_p)) is 29.1 J/mol·K. How much he...
At constant pressure, the molar heat capacity of nitrogen gas ((C_p)) is 29.1 J/mol·K. How much he...
The lattice enthalpy of NaCl is +788 kJ/mol and the enthalpy of hydration of its ions is -784 kJ/mol...
The lattice enthalpy of NaCl is +788 kJ/mol and the enthalpy of hydration of its ions is -784 kJ/mol...
About This Question
- Subject
- chemistry
- Chapter
- chemical thermodynamics
- Topic
- gibbs free energy
- Difficulty
- Medium
- Year
- 2025
Solution
Correct Answer:
ΔH < 0, ΔS > 0
Spontaneity is determined by the Gibbs Free Energy change: ΔG=ΔH−TΔS. For a reaction to be spontaneous, ΔG must be negative.
- If ΔH<0 (Exothermic) and ΔS>0 (Increased entropy), then: ΔG=(−ve)−T(+ve).
- Since T (absolute temperature) is always positive, ΔG will be negative at any temperature. This ensures spontaneity under all conditions.
This medium difficulty chemistry question is from the chapter chemical thermodynamics, covering the topic of gibbs free energy. It appeared in the 2025 exam.
Looking for more practice? Explore all chemistry questions or browse chemical thermodynamics questions on RankGuru.