For an ideal solution, the total vapor pressure varies _____________ with the composition (expressed as mole fraction)?

Related Mcqs:

1. The vapor pressure of the solvent decreased by 10 mm Hg, when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent, if the decrease in vapor pressure of the solvent is required to be 20 mm Hg ?

   A. 0.2
   B. 0.1
   C. 0.4
   D. 0.6

2. The ratio of existing moles of vapor per mole of vapor free gas to the moles of vapor that would be present per mole of vapor free gas, if the mixture were saturated at the existing temperature & pressure, is termed as the_____________________?

   A. Relative humidity
   B. Relative saturation
   C. Percentage saturation
   D. None of these

3. What is the total pressure exerted by a mixture of 0.45 kg mole of benzene, 0.44 kg mole of toluene and 0.23 kg mole of o-xylene at 100°C, if their vapor pressures at 100°C are 1340, 560 and 210 mmHg respectively ?

   A. 756.2
   B. 780.5
   C. 801.5
   D. 880.5

4. A very dilute solution is prepared by dissolving ‘x1’ mole of solute in ‘x2’ mole of a solvent. The mole fraction of solute is approximately equal to_________________?

   A. x1/x2
   B. x2/x1
   C. 1 – (x1/x2)
   D. 1/x2

5. Raoult’s law states that ‘the equilibrium vapor pressure that is exerted by a component in a solution is proportional to the mole fraction of that component’. This generalisation is based on the assumption that the________________?

   A. Sizes of the component molecules are approximately equal
   B. Attractive forces between like and unlike molecules are approximately equal
   C. Component molecules are non-polar and no chemical combination or molecular association
   between unlike molecules takes place in the formation of the solution
   D. All A., B. & C.

6. According to Raoult’s law, “The vapor pressure exerted by component in a solution is proportional to the mole fraction of that component.” Raoult’s law is not applicable under the following assumption/condition?

   A. No component is concentrated at the surface of the solution
   B. The component molecules are non polar and are of almost equal size
   C. In the formation of solution, chemical combination/molecular association between unlike
   molecules takes place
   D. The attractive forces between like and unlike molecules are almost equal

7. Vapor pressure of a solution is proportional to (where, Sv and St are mole fraction of solvent and solute respectively) ?

   A. Sv
   B. 1/St
   C. St
   D. 1/Sv

8. A vapor whose partial pressure is less than its equilibrium vapor pressure is called the _____________ vapor?

   A. Saturated
   B. Superheated
   C. Unsaturated
   D. Dry gaseous

9. The accumulation in a steady state combustion process, burning 1 kg mole of carbon with 1 kg mole of oxygen thereby producing 1 kg mole of carbon dioxide, is _____________ kg mole?

   A. 1
   B. 0
   C. 16
   D. 44

10. The vapor pressures of benzene and toluene are 3 and 4/3 atmospheres respectively. A liquid feed of 0.4 moles of benzene and 0.6 moles of toluene is vaporised. Assuming that the products are in equilibrium, the vapor phase mole fraction of benzene is_________________?

    A. 0.4
    B. 0.6
    C. 0.8
    D. 0.2