Absa 4b Final Exam, Practice Exam And Study Guide (3 VERSIONS) NEWEST
2026 (GRADED A+ 100% DETAILED VERIFIED ANSWERS)
Which of the following is a thermodynamic property of heat?
a) entropy
b) enthalpy
c) density
d) volume
e) all of the above - ANSWER-E
The property which has to be known for the calculation of the size of control valve and piping
etc, is
a) specific volume
b) enthalpy
c) refrigerating effect
d) density
e) boiling point - ANSWER-D
The refrigerating effect of a refrigerant is
a) equal to its latent heat of vaporization
b) greater than its latent heat of vaporization
c) less than its latent heat of vaporization
d) equal to its specific heat capacity
,e) equal to its specific volume - ANSWER-A
The standard refrigeration cycle is used to compare refrigerants and machines operating
under comparable conditions. These standard conditions are:
a) 1030 kPa and atmospheric pressure
b) 30 degrees Celsius condensing and -15 degrees Celsius evaporating
c) 30 kPa and atmospheric pressure
d) -30 degrees Celsius condensing and 15 degrees Celsius evaporating
e) 30 kPa and atmospheric temperature - ANSWER-B
The latent heat of fusion of ice
a) is the sensible heat required to melt ice
b) is 335 kJ per 1 kg
c) is 335 kJ per 1 ton
d) is the latent heat required to evaporate ice
e) is 4.2 kJ per gram - ANSWER-B
The ability of a refrigerant to be dissolved into oil and vice versa is called
a) moisture reaction
b) enthalpy
c) density
d) leakage tendency
e) miscibility - ANSWER-E
,Which of the following is not a physical property of
refrigerants?
a) Toxicity
b) Odour
c) Leakage tendency
d) Density
e) Explosiveness - ANSWER-D
Ammonia is the only commonly used refrigerant which has the physical property of
a) miscibility
b) enthalpy
c) flammability
d) density
e) low condensing pressure - ANSWER-C
Molecular mass is a dependent factor in which of the following physical properties?
a) miscibility
b) leakage tendency
c) toxicity
d) flammability
e) explosiveness - ANSWER-B
Freon 22 refrigerant
a) is not miscible with oil
, b) is mostly used in packing plants
c) is corrosive on copper
d) is corrosive on aluminum
e) is a heat transferring medium
Compression Refrigeration Systems - ANSWER-E
Which of the following are principal parts in a closed cycle compression refrigeration
system?
i) Absorber
ii) Evaporator
iii) Compressor
iv) Condenser
a) both i and ii
b) iii only
c) i, ii, iv
d) ii, iii, iv
e) i, ii, iii - ANSWER-D
Raising the condensing point (saturation temperature) of the refrigerant vapour above the
temperature of the cooling medium is the function of the
a) compressor
b) condenser
c) evaporator
2026 (GRADED A+ 100% DETAILED VERIFIED ANSWERS)
Which of the following is a thermodynamic property of heat?
a) entropy
b) enthalpy
c) density
d) volume
e) all of the above - ANSWER-E
The property which has to be known for the calculation of the size of control valve and piping
etc, is
a) specific volume
b) enthalpy
c) refrigerating effect
d) density
e) boiling point - ANSWER-D
The refrigerating effect of a refrigerant is
a) equal to its latent heat of vaporization
b) greater than its latent heat of vaporization
c) less than its latent heat of vaporization
d) equal to its specific heat capacity
,e) equal to its specific volume - ANSWER-A
The standard refrigeration cycle is used to compare refrigerants and machines operating
under comparable conditions. These standard conditions are:
a) 1030 kPa and atmospheric pressure
b) 30 degrees Celsius condensing and -15 degrees Celsius evaporating
c) 30 kPa and atmospheric pressure
d) -30 degrees Celsius condensing and 15 degrees Celsius evaporating
e) 30 kPa and atmospheric temperature - ANSWER-B
The latent heat of fusion of ice
a) is the sensible heat required to melt ice
b) is 335 kJ per 1 kg
c) is 335 kJ per 1 ton
d) is the latent heat required to evaporate ice
e) is 4.2 kJ per gram - ANSWER-B
The ability of a refrigerant to be dissolved into oil and vice versa is called
a) moisture reaction
b) enthalpy
c) density
d) leakage tendency
e) miscibility - ANSWER-E
,Which of the following is not a physical property of
refrigerants?
a) Toxicity
b) Odour
c) Leakage tendency
d) Density
e) Explosiveness - ANSWER-D
Ammonia is the only commonly used refrigerant which has the physical property of
a) miscibility
b) enthalpy
c) flammability
d) density
e) low condensing pressure - ANSWER-C
Molecular mass is a dependent factor in which of the following physical properties?
a) miscibility
b) leakage tendency
c) toxicity
d) flammability
e) explosiveness - ANSWER-B
Freon 22 refrigerant
a) is not miscible with oil
, b) is mostly used in packing plants
c) is corrosive on copper
d) is corrosive on aluminum
e) is a heat transferring medium
Compression Refrigeration Systems - ANSWER-E
Which of the following are principal parts in a closed cycle compression refrigeration
system?
i) Absorber
ii) Evaporator
iii) Compressor
iv) Condenser
a) both i and ii
b) iii only
c) i, ii, iv
d) ii, iii, iv
e) i, ii, iii - ANSWER-D
Raising the condensing point (saturation temperature) of the refrigerant vapour above the
temperature of the cooling medium is the function of the
a) compressor
b) condenser
c) evaporator
