SLIDE 1
DG
Chemical potential
At equilibrium chemical potentials are equivalent.
CEM 484 Chemical Thermodynamics 2
Chemical Thermodynamics D G Chemical potential At equilibrium - - PowerPoint PPT Presentation
Chemical Thermodynamics D G Chemical potential At equilibrium - - PowerPoint PPT Presentation
Chemical Thermodynamics D G Chemical potential At equilibrium chemical potentials are equivalent. Chemical Thermodynamics CEM 484 2 Clapeyron Equation Liquid-gas equilibrium Applies to all three equilibrium lines in phase
SLIDE 2
SLIDE 3
Clapeyron Equation
Liquid-gas equilibrium
Applies to all three equilibrium lines in phase diagram.
CEM 484 Chemical Thermodynamics 3
SLIDE 4
Example liquid-solid
Given that rCO2
l = 0.78 g/mL and rCO2 s = 1.53 g/mL.
What is the temperature of the solid – liquid equilibrium at 100 bar pressures. DfusH = 8.33kJ/mol
CEM 484 Chemical Thermodynamics 4
SLIDE 5
Example liquid-solid
Given that rCO2
l = 0.78 g/mL and rCO2 s = 1.53 g/mL.
What is the temperature of the solid – liquid equilibrium at 100 bar pressures. DfusH = 8.33kJ/mol.
Solid-liquid equilibrium line is nearly vertical
CEM 484 Chemical Thermodynamics 5
SLIDE 6
Example solid-gas
For the solid-gas equilibrium at 1 bar what is the temperature of dry ice in equilibrium with its vapor.
CEM 484 Chemical Thermodynamics 6
SLIDE 7
Example solid-gas
For the solid-gas equilibrium at 1 bar what is the temperature of dry ice in equilibrium with its vapor.
Results in Clausius Clapeyron equation
CEM 484 Chemical Thermodynamics 7
SLIDE 8
Example liquid-gas
For the liquid-gas the same assumptions can be made.
If the triple point is known, DvapH, DfusH, rs, and rl the phase diagram can be calculated
CEM 484 Chemical Thermodynamics 8
SLIDE 9
Iclicker
The vapor pressure (in Pa) for solid and liquid UF6 are given by:
What is the pressure of the triple point (units of kPa)?
A – P < 0
B – P = between 0 and 45
C – P = between 45 and 95
D – P = between 95 and 145
E – P > 145
CEM 484 Chemical Thermodynamics 9
T P T P
l s
/ 9 . 3479 254 . 22 ln / 5 . 5893 411 . 29 ln
SLIDE 10
Chemical potential
Calculate chemical potential at other T and P.
CEM 484 Chemical Thermodynamics 10