Short Answer TypeVapour pressures of pure acetone and chloroform at 328 k are 741.8 nm Hg and 632.8 mm Hg respectively. Assuming that they form ideal solution over the entire range of composition, plot Ptotal , Pchlroform and Pacelone as a function of Xactone. The experimental date observed for different composition of mixture is:
|
100 x xacetone |
0 |
11.8 |
23.8 |
36.0 |
50.8 |
58.2 |
64.5 |
72.1 |
|
Pacetone / mm Hg
|
0 |
54.9 |
110.1 |
202.4 |
327.7 |
405.9 |
454.1 |
521.1 |
|
Pchloroform/ mm Hg |
632.8 |
548.1 |
469.4 |
359.7 |
257.7 |
193.6 |
161.2 |
120.7 |
Plot this data also on the same graph paper, indicate whether it has positive deviation or negative deviation from the ideal solution.
Long Answer TypeAnswer:
Raoult’s law states that the partial vapour pressure of a component of a solution at a given temperature is equal to the product of the vapour pressure of the pure component at that temperature and its mole fraction in the solution.
Positive Deviation from Raoult’s law: In those non-ideal solutions, when partial pressure of component ‘A’ in the mixture of ‘A’ and ‘B’ is more than that calculated from Raoult’s law. Similarly, the partial vapour pressure of component ‘B’ can be higher than calculated from Raoult’s law. This type of deviation from ideal behaviour is called positive deviation from Raoult’s law, e.g., water and ethanol, chloroform and water, ethanol and CCl4, methanol and chloroform, benzene and methanol, acetic acid and toluene, acetone and ethanol, methanol and H2O.
For positive deviation ΔHmixing > 0.
Short Answer TypeLong Answer TypeShort Answer TypeLong Answer Type
Switch
