Difference between revisions of "Thermodynamics"

From AutoMeKin
Jump to navigation Jump to search
(Phase diagram of an ideal solution at fixed temperature)
(Phase diagram of an ideal solution at fixed temperature)
Line 107: Line 107:
 
The number of moles in each phase (liquid or vapor) can be obtained from the lever rule:
 
The number of moles in each phase (liquid or vapor) can be obtained from the lever rule:
 
<center>
 
<center>
<math>n^l\bar{BK}=n^v\bar{KR}</math>
+
<math>n^l\overline{BK}=n^v\overline{KR}</math>
 
</center>
 
</center>
  

Revision as of 07:26, 26 April 2019

Two-component vapor-liquid equilibrium

Phase diagram of an ideal solution at fixed temperature

The following plot shows the vapor-liquid phase diagram for a binary ideal mixture (components: A and B). The vapor pressures of the pure substances are [math]p_A^*[/math] and [math]p_B^*[/math], respectively.

The blue curve shows the vapor pressure [math]p[/math] of the mixture as a function of the mole fraction of A in the liquid [math]x_A^l[/math]:

[math]p=p_B^*+(p_A^*-p_B^*)x_A^l[/math]

The red curve shows the vapor pressure [math]p[/math] of the mixture as a function of the mole fraction of A in the vapor [math]x_A^v[/math]:

[math]p=\dfrac{p_A^*p_B^*}{p_A^*-(p_A^*-p_B^*)x_A^v}[/math]

In the example below [math]p_A^*=1[/math] (a.u.) and the value of [math]p_B^*[/math] can be changed moving the slider below.


slider.py example


The number of moles in each phase (liquid or vapor) can be obtained from the lever rule:

[math]n^l\overline{BK}=n^v\overline{KR}[/math]


slider.py example