If „f’ is defined as above, then which of the following applies to a feed at dew point ?

Related Mcqs:

1. On moving the feed line (q-line) from saturated liquid feed (vertical position) to saturated vapor feed (horizontal feed), if the slope of both the operating lines are to be increased, then it will result in______________________?

   A. Greater degree of separation with a fixed number of trays
   B. Increased reboiler load
   C. Increased reflux ratio
   D. None of these

2. A mixture of 10% C6H6 vapour in air at 25°C and 750 mm Hg has a dew point of 20°C. Its dew point at 30°C and 700 mm Hg will be around _______________ °C?

   A. 21.7
   B. 20
   C. 27.3
   D. 18.7

3. For the same feed, feed quality and separation (in a distillation column), with the increase of total pressure, the number of ideal plates will_____________________?

   A. Increase
   B. Decrease
   C. Remain same
   D. Data insufficient, can’t be predicted

4. If f = moles of vapour present per mole of feed, then the slope of feed line is (McCabe- Thiele method) ________________________?

   A. (1 – f)/f
   B. – (f – 1)/f
   C. -1/f
   D. -f/(1 – f)

5. One mole feed of a binary mixture of a given composition is flash vaporised at a fixed P and T. If Raoult’s law is obeyed, then changing the feed composition would effect ?

   A. The product composition but not the fraction vaporised
   B. The product composition as well as the fraction vaporised
   C. The fraction vaporised but not the product composition
   D. Neither the product composition nor the fraction vaporised

6. When the feed to a distillation column is a saturated liquid, slope of the feed line is_____________________?

   A. Zero
   B. Unity
   C. Infinity
   D. None of these

7. In distillation where q is defined as the moles of liquid flow in the stripping section per mole of feed introduced, for saturated liquid feed____________________?

   A. q > 1
   B. q < 1
   C. q = 1
   D. q = 0

8. Dew point of an air-water vapor mixture_________________?

   A. Decreases with decrease in pressure
   B. At constant humidity & total pressure is fixed
   C. Corresponding to any point on the humidity chart is obtained by projecting a line through this
   point parallel to the temperature axis and to the saturation curve
   D. All A , B. & C.

9. The dew point of a saturated gas phase equals the ________________ temperature?

   A. Gas
   B. Room
   C. Wet bulb
   D. None of these

10. Air at a particular humidity is heated in a furnace. The new dew point_____________________?

    A. Decreases
    B. Increases
    C. Depends on the extent of heating
    D. Remain unchanged