CHM2046 - Chemistry Fundamentals II: Free Energy and Thermodynamics Part 2

These flashcards cover the key concepts from Chapter 19 on Free Energy and Thermodynamics from the lecture notes.

What is the Heat Death of the universe?

A state of no thermodynamic free energy.

What equation defines the change in entropy (∆S) when a system exchanges heat (q) at constant temperature (T)?

∆S = q_rev / T.

What does q_rev represent in the equation for entropy changes?

The heat exchanged with the surroundings in a reversible process.

What is the condition for a process to be considered reversible?

It can be reversed by an infinitesimal change in a variable such that both the system and surroundings can be restored to their original states.

What is the code for calculating the change in entropy when 1 mol of ice melts at its melting point?

∆S = q_rev / T, with q = 6.02 kJ/mol and T = 273 K.

How does the entropy change for a system when ice melts?

The value of ∆S is positive, indicating an increase in entropy from solid to liquid.

What is the change in entropy (∆S) when acetone vaporizes from a liquid to a gas at its boiling point of 56.1 °C?

Calculated using ∆S = q_rev / T.

What are the First and Second Laws of Thermodynamics about energy and entropy?

Energy is conserved (First Law); spontaneous processes increase total entropy (Second Law).

How does an exothermic process affect the entropy of the surroundings?

It increases the entropy of the surroundings.

How does temperature affect the change in entropy of surroundings?

At low temperatures, the decrease in system entropy can be overcome by the increase in surroundings entropy.

What is Gibbs Free Energy and its significance?

Gibbs free energy is the maximum work energy that can be released to the surroundings; it determines the spontaneity of a process.

How is Gibbs Free Energy related to spontaneous processes?

A negative ΔG indicates a spontaneous process, as ΔSuniv is positive.

How is the relationship between enthalpy and entropy changes expressed for a system?

∆Gsys = ∆Hsys - T∆S_sys.