Chemical Process Calculation Multiple Choice Questions & Answers (MCQs) focuses on “Vaporization”.
1. In a vaporization process __________ changes to _________
a) Vapor, liquid
b) Vapor, solid
c) Solid, Vapor
d) Liquid, Vapor
Answer: d
Clarification: In vaporization process liquid changes to vapor.
2. Vaporization starts at __________ point.
a) Dew point
b) Bubble point
c) Triple point
d) None of the mentioned
Answer: b
Clarification: At Bubble point liquid starts evaporating which is the point at which vaporization starts.
3. Heating a liquid at constant pressure can definitely cause____________
a) Vaporization
b) Condensation
c) Boiling
d) None of the mentioned
Answer: a
Clarification: Heating a liquid at constant pressure can definitely cause Vaporization.
4. Vaporization temperature of water at standard conditions is _______________ Degree Celsius.
a) 100
b) 200
c) 300
d) 400
Answer: a
Clarification: Vaporization temperature of water at standard conditions is 100 Degree Celsius.
5. Amount of water vapor in the air increases as the dew point temperature ______________
a) Increases
b) Decreases
c) Remains same
d) None of the mentioned
Answer: a
Clarification: Amount of water vapor in the air increases as the dew point temperature increases.
6. When the air temperature rises, the saturation vapor pressure
a) Increases
b) Decreases
c) Remains same
d) None of the mentioned
Answer: a
Clarification: When the air temperature rises, the saturation vapor pressure increases.
7. When the air temperature rises the saturation mixing ratio
a) Increases
b) Decreases
c) Remains same
d) None of the mentioned
Answer: a
Clarification: When the air temperature rises the saturation mixing ratio increases.
8. Most heat energy is required in the following process?
a) Sublimation
b) Evaporation
c) Condensation
d) None of the mentioned
Answer: a
Clarification: Sublimation needs more energy than evaporation and condensation.
9. The fraction of water vapor at 300 K and 8 atm is 0.8. Calculate the fraction of water vapor at the same temperature and 1 atm pressure?
a) 0.1
b) 0.2
c) 0.3
d) 0.4
Answer: a
Clarification: Fraction of water vapor at 300 K and 1 atm pressure is 0.8/8 = 1.
10. What is the fraction of water vapor at 300 K and 1 atm, if the fraction of water vapor at the same pressure is 0.8 and temperature is 400 K?
a) 0.2
b) 0.4
c) 0.6
d) 0.8
Answer: c
Clarification: Fraction of water vapor at 127oC and 1 atm = 0.8*300/400 = 0.6.