4.2 Enthalpy, Entropy and Free Energy Flashcards
Entropy, S (J K⁻¹ mol⁻¹)
A measure of the disorder or randomness of a system.
Standard Entropy, Sᶱ
The entropy content of one mole of a substance under standard conditions (298K and 1 atm pressure) and in standard state.
Feasable Reaction
A reaction in which ΔG < 0.
Hess’ Law
The total enthalpy change of a reaction is independent of route taken, provided that initial and final conditions are the same.
Entropy Change, ΔSᶱ
ΔSᶱ = ΣSᶱ ᵖʳᵒᵈᵘᶜᵗˢ - ΣSᶱ ʳᵉᵃᶜᵗᵃⁿᵗˢ
The sum of entropies of products minus the sum of entopies of reactants understandard conditions.
Standard Free Energy Change, ΔGᶱ (kJ mol⁻¹)
The standard free energy change is used to deduce wethetr or ont a reaction is feasable
ΔGᶱ = ΔHᶱ - TΔSᶱ