POWER ENGINEERING 3B2 - CHAPTER
10 EXAM QUESTIONS AND ANSWERS.
VERIFIED 2026.
A refrigerant may be defined as a:
a. A liquid that absorbs heat at high pressure and gives up heat at low pressure.
b. A fluid that absorbs heat at a low temperature & pressure and gives up heat by condensing at
a higher temperature & pressure.
c. A fluid that absorbs heat at a high pressure.
d. Medium for creating heat.
e. A fluid that absorbs heat at a high temperature & pressure and gives up heat by condensing
at a lower temperature & pressure. - ANS B
A good refrigerant should require a _________________.
a. low latent heat value
b. high temperature boiling point
c. high condensing temperature
d. high condensing pressure
e. large amount of heat to evaporate - ANS E
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Ammonia refrigerant will ___________________________.
a. mix easily with mineral oils
b. not mix with mineral oils
c. mix with oils when heated
d. not mix with water
e. be added with oil for lubrication purposes - ANS B
A good refrigerant should have _____________________.
a. a high net refrigeration effect
b. a low net refrigeration effect to save power
c. a medium refrigeration effect
d. a high condensing pressure
e. a condensing temperature - ANS A
Group 3 refrigerants are __________________________.
a. extremely flammable
b. moderately flammable
c. non flammable
d. moderately explosive
e. non explosive - ANS A
Group 1 refrigerants ______________________________.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, a. are quite poisonous
b. are easily ignited
c. have the highest latent heat value
d. are considered the safest
e. are moderately toxic - ANS D
NH3 (R-717) refrigerant ___________________________.
a. will not cause corrosion to metals
b. is non-toxic
c. is corrosive in the presence of water to nonferrous metals
d. is very expensive
e. is extremely explosive - ANS C
R-12 and R-22 refrigerants are ____________________.
a. known as halocarbons or Freons
b. used only in commercial establishments
c. extremely toxic
d. used only in indirect systems
e. extremely explosive - ANS A
The heat necessary to evaporate a liquid refrigerant in mechanical refrigeration is
_______________________.
a. sensible heat
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
10 EXAM QUESTIONS AND ANSWERS.
VERIFIED 2026.
A refrigerant may be defined as a:
a. A liquid that absorbs heat at high pressure and gives up heat at low pressure.
b. A fluid that absorbs heat at a low temperature & pressure and gives up heat by condensing at
a higher temperature & pressure.
c. A fluid that absorbs heat at a high pressure.
d. Medium for creating heat.
e. A fluid that absorbs heat at a high temperature & pressure and gives up heat by condensing
at a lower temperature & pressure. - ANS B
A good refrigerant should require a _________________.
a. low latent heat value
b. high temperature boiling point
c. high condensing temperature
d. high condensing pressure
e. large amount of heat to evaporate - ANS E
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Ammonia refrigerant will ___________________________.
a. mix easily with mineral oils
b. not mix with mineral oils
c. mix with oils when heated
d. not mix with water
e. be added with oil for lubrication purposes - ANS B
A good refrigerant should have _____________________.
a. a high net refrigeration effect
b. a low net refrigeration effect to save power
c. a medium refrigeration effect
d. a high condensing pressure
e. a condensing temperature - ANS A
Group 3 refrigerants are __________________________.
a. extremely flammable
b. moderately flammable
c. non flammable
d. moderately explosive
e. non explosive - ANS A
Group 1 refrigerants ______________________________.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, a. are quite poisonous
b. are easily ignited
c. have the highest latent heat value
d. are considered the safest
e. are moderately toxic - ANS D
NH3 (R-717) refrigerant ___________________________.
a. will not cause corrosion to metals
b. is non-toxic
c. is corrosive in the presence of water to nonferrous metals
d. is very expensive
e. is extremely explosive - ANS C
R-12 and R-22 refrigerants are ____________________.
a. known as halocarbons or Freons
b. used only in commercial establishments
c. extremely toxic
d. used only in indirect systems
e. extremely explosive - ANS A
The heat necessary to evaporate a liquid refrigerant in mechanical refrigeration is
_______________________.
a. sensible heat
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
