Class 11 Chemistry Chapter 5 Chemical Thermodynamics – Revision Notes

Quick revision notes for Class 11 Chemistry Chapter 5 (Chemical Thermodynamics). These Class 11 Chemistry Chapter 5 notes are ideal for quick revision just before exams.

Systems and First Law

• Open, closed, isolated systems.
• ΔU=q+w.

Enthalpy

• H=U+PV; ΔH=q_p.
• Exothermic: ΔH<0; Endothermic: ΔH>0.
• Hess’s law: ΔH is path-independent (state function).

Entropy and Free Energy

• Entropy: measure of disorder; increases in spontaneous processes (isolated system).
• ΔG=ΔH−TΔS; ΔG<0 spontaneous, ΔG=0 equilibrium.

One-Line Summary

Chemical thermodynamics uses enthalpy, entropy, and Gibbs free energy to determine whether a chemical process will occur spontaneously under given conditions.

Written by Satish

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