Practice Exams ChE - 34

1. In a batch process, 10,000 lbs of 205 solution of acetone in water are distilled. Water residue contains 50 lb acetone, while the distillate contains 10% water. What is the total weight of the distillate?
a. 6,584
b. 1,486
c. 2,167
d. 3,958
e. none of these

2. A laboratory leaf filter is run at constant rate. The initial pressure after 30 minutes is 65 psig during which 5 ft^3 of filtrate is collected. The resistance of the filter medium in terms of ft3 of filtrate is:
a. 0.42
b. 0.95
c. 2
d. 3
e. none of these

3. A plate and frame press delivers 50 liters of filtrate in one hour at a constant pressure of 50 psig. The washing time at constant pressure of 20 psig using 10 liters of wash water is :
a. 1.6
b. 3.2
c. 4
d. 2.5
e. none of these

4. From what mineral is radium obtained?
a. limestone
b. rutile
c. pitch blende
d. hematite
e. none of these

5. In gas absorption, if the mass transfer coefficient in the liquid phase is very much greater than the mass transfer coefficient in the gas phase, which of the following is not true?
a. Liquid film resistance is negligible.
b. Mass transfer operation is controlled by the gas phase resistance.
c. Solute in the gas mixture is very soluble in the liquid.
d. The liquid film resistance controls the rate of mass transfer.
e. None of these