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Thermodynamics laboratory

Connect energy profiles, Hess cycles, calorimetry and Gibbs free energy in one live workspace.

SchoolLive

Scientific learning path

  1. 01UnderstandLive
  2. 02ExploreLive
  3. 03ExperimentLive
  4. 04ObserveLive
  5. 05ExplainLive
  6. 06ApplyLive
  7. 07TestLive
Explanation mode
ReactantsProductsEₐ

Description of this simulation

The reaction enthalpy is -92 kJ mol⁻¹ and the forward activation energy is 175 kJ mol⁻¹.

Quick test · 3 questions
1. Which statement is evidence from this simulation?
2. How should you test the effect of one control?
3. Why read the model notes?
ΔH
-92 kJ mol⁻¹
Eₐ
175 kJ mol⁻¹

Learning guide

Learning objective
Connect energy diagrams and measured heat to enthalpy, entropy and spontaneity.
Core equation
q = mcΔT; ΔG = ΔH − TΔS; ΔHtarget = Σ(multiplier × ΔH)
Why the result changes
Changing temperature alters the TΔS term; changing an equation direction or multiplier changes its enthalpy contribution.
Try this challenge
Find a temperature at which the sign of ΔG changes.
Sources
IUPAC Gold Book; Atkins' Physical Chemistry; CRC Handbook

What this model shows — and what it simplifies

Educational Model

The laboratory keeps heat, enthalpy, entropy and free energy distinct and uses explicit units in every calculation.

Where do we see this in real life?

Thermodynamic balances govern engines, refrigeration, batteries, metabolism and industrial heat management.

Explain this result

Scientific review record

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v1 bundled
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