Week 4 Entropy and Thermodynamic Potentials Flashcards
what is true of entropy of a closed system (universe)
entropy of an isolated system can never decrease
what is the heat capacity entropy eqn
CxdT = TdS
what is the fundamental thermodynamic relation (FTR) eqn for a fluid
dE = TdS - PdV
what does FTR suggest
energy is a function of entropy and volume
what is the infinitesimal helmholtz free energy eqn
dF = -SdT - PdV
where F = E - TS
define free energy
energy available to perform thermodynamic work at constant temp
what is true of Helmholtz energy
it can never increase and can only decrease for irreversible processes
what happens to helmholtz energy at eqm
it is minimised for the given T&V conditions
what are the Gibbs free energy eqns
G = E - TS + PV ΔG = ΔE - TΔS + PΔV =< W + PΔV
define Gibbs free energy
energy available to be converted into non-volumetric work at constant P and T
what is the Gibbs enthalpy eqn
ΔG = ΔH - TΔS
what are the four Maxwell relation eqns
MR1 (dT/dV)s = -(dP/dS)v
MR2 (dP/dT)v = (dS/dV)t
MR3 (dT/dP)s = (dV/dS)p
MR4 (dS/dP)t = (dV/dT)p
