A system comprised of chloroform, 1,4-dioxane, and ethanol exists as a two-phase vapor/liquid system at 50°C and 55 kPa. After the addition of some pure ethanol, the system can be returned to two-phase equilibrium at the initial T and P. In what respect has the system changed, and in what respect has it not changed?
(a) How many phase-rule variables in addition to T and P must be chosen so as to fix the compositions of both phases?
(b) If the temperature and pressure are to remain the same, can the overall composition of the system be changed (by adding or removing material) without affecting the compositions of the liquid and vapor phases?
(a) The phase rule tells us that the degrees of freedom of the system are
F =2 -? +N =2 -2 +3 =3
Because there are 3 total degrees of freedom, one more phase-rule variable must be specified, in addition to T and P, to fix the values of all of the intensive variables in the system (including the compositions of both phases).
(b) Adding or removing liquid having the composition of the liquid phase or adding or removing vapor having the composition of the vapor phase does not change the phase compositions, and does not alter the intensive state of the system.
You might also like to view...
What is meant by the term "blowdown"?
What will be an ideal response?
A line used for transferring distances is called a:
a. Cutting plane line b. Construction line c. Extension line d. Edge line e. Reference line
Technician A says that in the event of a loss of chassis electricity, the shift finger on an Eaton AMT can no longer be moved. Technician B says that an Eaton AMT will default to mechanical shifting in the event of a loss of electrical supply. Who is correct?
A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B
The most effective means of forcing a lexan window is by using a(n):
A. flat-head axe B. oxyacetylene torch C. rotary saw equipped with a carbide-tipped blade D. reciprocating saw