Refrigerants Flashcards
The refrigerating effect of a refrigerant is:
A) Greater than its latent heat of vaporization
B) Equal to its specific volume
C) Equal to its latent heat of vaporization
D) Less than its latent heat of vaporization
E) Equal to its specific heat capacity
C) Equal to its latent heat of vaporization
Which of the following characteristics is common in all of the group B refrigerants?
A) Low flammability B) Average flammability C) High flammability D) High toxicity E) Low toxicity
D) High toxicity
The ability of a refrigerant to be dissolved into oil and vice versa is called:
A) Density B) Moisture reaction C) Enthalpy D) Miscibility E) Leakage tendency
D) Miscibility
Which of the following is not a physical property of refrigerants?
A) Leakage tendency B) Toxicity C) Oxidization D) Odour E) Explosiveness
C) Oxidization
Molecular mass is a dependent factor in which of the following physical properties of a refrigerant?
A) Leakage tendency B) Explosiveness C) Miscibility D) Toxicity E) Flammability
A) Leakage tendency
Group “A1” refrigerants as found in the current code are:
A) Toxic and non-flammable B) Non-flammable and non-toxic C) Low-flammable and toxic D) High-toxic and flammable E) Low-toxic and flammable
B) Non-flammable and non-toxic
The standard refrigeration cycle is used to compare refrigerants and machines operating under comparable conditions. These standard conditions are:
A) 30°C and atmospheric pressure
B) 103°C and atmospheric pressure
C) 30°C for the condenser and -15°C for the evaporator
D) -30°C for the condenser and 15°C for the evaporator
E) 103 kPa and ambient temperature
C) 30°C for the condenser and -15°C for the evaporator
The property which must be known to calculate the size of control valves piping, etc. is:
A) Density B) Refrigerating effect C) Boiling point D) Specific volume E) Enthalpy
A) Density
R-134a (1, 1, 1, 2 - tetrafluoroethane) is non-toxic and non-flammable. Which of the following group does it belong to?
A) Group A1 B) Group B4 C) Group A2 D) Group A3 E) Group B2
A) Group A1
The practical refrigerating effect of a refrigerant is:
A) Equal to its latent heat of vaporization
B) Equal to its specific volume
C) Greater than its latent heat of vaporization
D) Equal to its specific heat capacity
E) Less than its latent heat of vaporization
E) Less than its latent heat of vaporization
According to the refrigeration tables which of the following is the corresponding temperature at an absolute pressure of 103.05 kPa for R717?
A) 115°C B) 10°C C) -75°C D) -33°C E) -101°C
D) -33°C
Which refrigerant is corrosive to copper, flammable, readily absorbs in water, is toxic, has the highest refrigerating effect?
A) Dichlorotetraflouoroethane R-114 B) Ammonia R-717 C) Freon R 134 D) Freon R-12 E) Freon R-22
B) Ammonia R-717
