12.4The Second and Third Laws of Thermodynamics
Section · module m68818
What this needs
Learn these first — this section will not make sense without them.
Nothing in the algebra book is a prerequisite for this section.
What this touches
Algebra that turns up here. Not a blocker, but this is where you will see it used.
ΔS° = ΣνS°(products) − ΣνS°(reactants) is the same subtract-one-weighted-sum-from-another pattern as ΔH from enthalpies of formation in chapter 9 — miss the overall subtraction and a reaction with decreasing entropy reads as increasing.
- Applies2.4Models and Applications
‘Will Ice Spontaneously Melt?’ substitutes into ΔSuniv = ΔSsys + qsurr/T at two different temperatures and compares the resulting signs — literal-formula evaluation where the payoff is a sign, not a magnitude.