Gibbs free energy
In thermodynamics, the Gibbs free energy is a thermodynamic potential that can be used to calculate the maximum amount of work, other than pressure–volume work, that may be performed by a thermodynamically closed system at constant temperature and pressure.
At a glance
Key signals
0% cross fields · reaches 4 more
- Chemistry
- Physical Chemistry
- Explanation
- Examples
- Misconception
- Sourced relations 2
- Attribution
Dependencies
What this concept builds on and what it makes possible — derived from the atlas’s dependency, causal and structural relations, not from every related edge.
Foundations · builds on
Gibbs free energydepends onEnthalpyEstablished
Gibbs free energy depends on enthalpy.
Mechanism: Gibbs free energy depends on enthalpy: it combines the heat change with the entropy change to predict whether a reaction runs spontaneously.
- Chemistry 2e (OpenStax) (2019) verifiedmoderate evidence
Gibbs free energydepends onEntropyEstablished
Gibbs free energy depends on Entropy.
Mechanism: Gibbs free energy combines enthalpy and entropy (ΔG = ΔH − TΔS) to predict whether a reaction runs spontaneously.
- Chemistry 2e (OpenStax) — demonstrates this case · verified · moderate evidence · Gibbs free energy combines enthalpy and the temperature-weighted entropy term (G = H − TS), so spontaneity depends on entropy. (Thermodynamics — Free Energy)
Structural role & consequence
Interpreted from the current atlas graph — what the connections mean, not just how many there are.
Currently dark in the atlas: no key date stored · 1 of 2 of its relations lack claim-level evidence.
atlas representation · Describes the current Thinking OS representation, not the state of the world.
Builds on 2 foundations (requires / depends-on / derived-from / emerges-from).
structural · Structural graph analysis — not a claim of importance, causation or history.
Exercises 2 annotated mental models — a concept that connects several thinking patterns.
curated · Curated annotations, not a derived measure.
Structural neighbourhood: 2 → 12 → 49 concepts reachable within 3 hops.
structural · Structural reach — being reachable is not the same as being understood.
cross-field
2 within-field, 0 cross-field
Strengths & constraints
Constraints
- No dated history stored — the atlas records no key date for this concept. atlas representation
Conditions
- Its dependency reading rests on 2 foundation relations. structural
Dependency radial
What this concept builds on (left) and what it makes possible (right) — derived from dependency and causal relations.
Seen through each discipline
How this concept sits in each of its fields — derived from its real connections in the graph, not asserted.
Formula
Predicts whether a process at constant temperature and pressure is spontaneous (ΔG < 0).
\Delta G— change in free energy\Delta H— enthalpy change\Delta S— entropy change
Source: Chemistry 2e (OpenStax)
Check yourself
A quick check against a common misconception. Nothing is scored — picking the tempting-but-wrong answer just flags an idea worth revisiting.
Which statement is correct?
A reaction with a negative ΔG happens quickly.
ΔG tells you only whether a reaction can happen, not how fast. Diamond turning to graphite has negative ΔG but takes eons — rate is set by activation energy, not ΔG.
Look for: Learner equates a spontaneous (ΔG<0) reaction with a fast one.
Related ideas to explore
Concepts that look related but are not yet connected here — candidates for a connection to reason about, not established links.
This idea also appears in…
The same structure shows up in other disciplines. These are real recurrences drawn from the graph — a starting point for asking “what carries over, and what changes?”
Trade-offs42 disciplines · 33 concepts
Entropy & irreversibility10 disciplines · 8 concepts
Concepts
shares a mental model · shares a mental model
shares a mental model
shares a mental model
shares a mental model
shares a mental model
shares a mental model
Gibbs free energy combines a reaction's heat change (enthalpy) and its disorder change (entropy) into one number that predicts direction: ΔG = ΔH − TΔS. If ΔG is negative the reaction can happen on its own; if positive it needs a push from outside.
Gibbs free energy G = H − TS is a thermodynamic potential whose change at constant temperature and pressure sets reaction spontaneity and the position of equilibrium (ΔG° = −RT ln K). It reconciles the drive toward lower enthalpy with the drive toward higher entropy, weighted by temperature.
Mental models at work here
Trade-offs
When getting more of one thing means accepting less of another, because resources or constraints are limited.
Ask what you give up (the opportunity cost) to gain what you want.
Entropy & irreversibility
Left alone, systems drift toward their most probable, most spread-out states — giving processes a direction in time that is hard to reverse.
Ask why a process only runs one way. Order can grow locally only by exporting more disorder elsewhere — and it always costs energy.
- Connects 2 other ideas across 2 disciplines.
- A cross-disciplinary bridge — its connections reach into 4 other fields.
- Most of its connections are of the “Dependency” kind.
- It exercises 2 reusable thinking patterns.
Derived from the graph’s real structure — observations, not a score.
Sources
- Wikipedia (English & German editions) verifiedmoderate evidence
- Wikidata verifiedmoderate evidence
- Chemistry 2e (OpenStax) (2019) verifiedmoderate evidence