thermodynamics 3 Flashcards
(8 cards)
What does it mean for a reaction to be thermodynamically favourable?
It means the change in Gibbs Free Energy (ΔG) is negative at constant temperature and pressure.
What happens at the equilibrium point of a reaction?
The free energy is at its minimum, and the composition of the mixture no longer changes.
Why doesn’t the system reach 100% conversion (ξ = 1) naturally?
Because it would increase the free energy, which is thermodynamically unfavourable unless energy is added.
What is the standard free energy change (ΔG⁰)?
It’s the difference in free energy between products and reactants under standard conditions (1 mol/L).
How can we determine the equilibrium constant K experimentally?
By measuring the concentrations of products and reactants, typically using spectroscopy.
What does the Second Law of Thermodynamics say about spontaneous processes?
Entropy of an isolated system increases (ΔS_total > 0) during a thermodynamically favourable change.
What condition marks the end of a reaction in thermodynamic terms?
When ΔG = 0, or the total entropy (S_total) is at a maximum.
How does free energy relate to solute concentration?
G = G⁰ + RT ln([X]) — where [X] is the concentration of the solute.
