Practice Exams ChE - 35

1. A furnace with glass float (s.g. = 2.165) gives a reading of 5 L/min for water flowing at a T=30 degC. If C2H5OH is flowing through the same flow meter, what will be the actual flow rate if the reading is 5 L/min?
a. 3.6
b. 7.0
c. 6.2
d. 7.8
e. none of these

2. A certain substance A is mixed with equal amounts of B and C. After 1000 seconds ½ of A has reacted. How much will be unreacted after 2000 seconds, if the reaction is 2nd order with respect to A?
a. 0.25 CAo
b. 1/3 CAo
c. 0.38 CAo
d. 0
e. none of these

3. The Buckingham Pi Theorem is applied to
a. Pressure-velocity relationships in compressible flow
b. Heat transfer by natural convection
c. Dimensional analysis of a physical system
d. Stability of control systems
e. None of these

4. The pipe size of a pneumatic conveyor to convey plastic pellets with bulk density of 30 lb/ft^3 using a blower with a capacity of 600 ft^3/min is ____ inches.
a. 3
b. 5
c. 8
d. 2
e. none of these

5. Crystals of Na2CO3.10 H2O are dropped into a saturated solution of Na2CO3 in H2O at 100 degC, what % of the Na2CO3 is in the Na2CO3.10 H2O.
Data at 100 degC = saturated solution is 31.2 % Na2CO3
Mw Na2CO3 = 106

6. A flotation modifier which assists in selectivity (sharpness of separation) or stop unwanted mineral from floating is
a. depressants
b. activators
c. alkalinity regulators
d. promoter
e. none

7. A cash flow refers to
a. the flow of money through a pipeline
b. the sum of positive and negative movements of cash
c. the rate of cash deposits and withdrawal in a bank
d. the assets and liabilities of a company
e. none of these

8. A pipe conducting superheated steam is lagged with several layers of insulation. The rate of radial heat flow:
a. decreases from inside to outside layer
b. increases from inside to outside layer
c. equal to each other
d. varies across each layer
e. none of these

9.
a. Sedimentation
b. Precipitation
c. Cooling
d. Activated Sludge Process
e. Chlorination
is a physical method of water treatment.

10. The degrees of freedom associated with a humidification process is
a. 1
b. 2
c. 3
d. 4
e. none of these