2/14/2024 ENTROPY & GIBBS FREE ENERGY REVIEW

Question 1

What drives reactions? Why do they happen?

Answer 1

ENERGY drives reactions

Question 2

Why do endothermic reactions occur if reactants are more stable than products? (if ΔH is positive)

Answer 2

Because change in entropy ΔS will often dominate change in enthalpy ΔH.

• The need to increase disorder (S) will cause reactions to take place!

Question 3

What are the three factors that determine if a reaction happens or not (spontaneity)?

Answer 3

1. Enthalpy (H)
2. Temperature (T)
3. Entropy (S)

Question 4

How can we predict spontaneity?

Answer 4

Gibb’s Free Energy (G)
ΔG = ΔH-TΔS

ΔG<0 Spontaneous
ΔG=0 Equilibrium
ΔG>0 Non-Spontaneous