How to Justify the Second Law of Thermodynamics – Part 1

The second law of thermodynamics establishes the concept of entropy as a physical property of a thermodynamic system.

In a natural thermodynamic process, the sum of the entropies of the interacting thermodynamic systems NEVER decreases.

The term ‘spontaneous’ has historically been used to describe processes for which the change in Gibbs free energy in the standard state, ΔG^Ѳ < 0. The phrase ‘thermodynamically favored’ is preferred instead so that common misunderstandings equating ’spontaneous’ with ‘suddenly’ or ‘without cause’ can be avoided.

Question:

A hand warmer produces heat when a concentrated Sodium acetate solution crystallizes spontaneously at constant pressure. What does the observed spontaneity (rather thermodynamic favorability) of the reaction imply?

Solution:

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ΔH^Ѳ = Change in enthalpy in the standard state, ΔS_uni^Ѳ = Change in entropy of the universe in the standard state

That makes sense❓ Let Chemaficionado know at mychemistryhomework@gmail.com❗

Reference:

Wikipedia Contributors. Entropy. Wikipedia. https://en.wikipedia.org/wiki/Entropy.