Bcit Exam Quizzes with Correct Verified
Answers
2
Heat supplied or taken away from a substance that causes a change of state without a change in
temperature is called
1) evaporative heat.
2) latent heat.
3) accumulated heat.
4) sensible heat.
5) convective heat.
3
Superheated refrigerant is refrigerant at saturation pressure, whose temperature is above the
1) conduction temperature.
2) fusion temperature.
3)saturation temperature.
4) compressor suction temperature.
5) sensible temperature.
3
Ammonia refrigerant
,1) is very miscible with refrigerant lubricating oil.
2) will dilute the oil in the crankcase.
3) is not miscible with refrigerant lubricating oil.
4) will not mix with water.
5) is miscible only with hot lubricating oil.
5
The ideal refrigerant should have a
1. low boiling point at atmospheric pressure.
2. low latent heat capacity.
3. low condensing pressure.
4. non-corrosive action on metals.
1)1, 2 and 4 only.
2) 1, 2 and 3 only.
3) 1 and 3 only.
4) 2 and 3 only.
5) 1, 3 and 4 only.
4
Refrigerants are identified by
1) chemical composition, specific gravity, trade name, freezing point.
2)density, chemical formula, common names, weight.
,3) saturation pressure, refrigerant number, weight, colour.
4) chemical formula, trade name, refrigerant number, chemical name.
5)trade name, refrigerant number, chemical formula, density.
1
A secondary refrigerant commonly employed in the cooling coils beneath an arena's ice surface
is
1) calcium chloride brine.
2) ammonia.
3) ammonium chloride.
4)Freon 12.
5) water.
4
The expansion (refrigerant control) valve in a refrigeration system is
1) between the compressor discharge and the compressor crankcase.
2) between the compressor and the condenser.
3) between the evaporator and the compressor.
4) between the receiver and the evaporator.
5) between the condenser and the receiver.
3
, To prevent damage due to entering liquid, reciprocating refrigeration compressors are equipped
with
1) a discharge relief valve.
2) suction line rupture discs.
3) spring-loaded safety heads.
4) a quick-closing suction valve.
5) discharge line rupture discs.
4
Actual mass = volumetric eff. x theoretical mass
= 0.75 x 8.28 kg/min
= 6.21 kg/min (Ans.)
The theoretical mass of refrigerant moved by a compressor is 8.28 kg/min. If the volumetric
efficiency is 75%, the actual mass moved is
1) 33.12 kg/min.
2) 11.04 kg/min.
3) 8.28 kg/min.
4) 6.21 kg/min.
5) 2.07 kg/min.
3
The function of the refrigeration condenser is to cool the hot compressed refrigerant
vapour until it condenses to a liquid. To do this, the condenser must remove both the heat
Answers
2
Heat supplied or taken away from a substance that causes a change of state without a change in
temperature is called
1) evaporative heat.
2) latent heat.
3) accumulated heat.
4) sensible heat.
5) convective heat.
3
Superheated refrigerant is refrigerant at saturation pressure, whose temperature is above the
1) conduction temperature.
2) fusion temperature.
3)saturation temperature.
4) compressor suction temperature.
5) sensible temperature.
3
Ammonia refrigerant
,1) is very miscible with refrigerant lubricating oil.
2) will dilute the oil in the crankcase.
3) is not miscible with refrigerant lubricating oil.
4) will not mix with water.
5) is miscible only with hot lubricating oil.
5
The ideal refrigerant should have a
1. low boiling point at atmospheric pressure.
2. low latent heat capacity.
3. low condensing pressure.
4. non-corrosive action on metals.
1)1, 2 and 4 only.
2) 1, 2 and 3 only.
3) 1 and 3 only.
4) 2 and 3 only.
5) 1, 3 and 4 only.
4
Refrigerants are identified by
1) chemical composition, specific gravity, trade name, freezing point.
2)density, chemical formula, common names, weight.
,3) saturation pressure, refrigerant number, weight, colour.
4) chemical formula, trade name, refrigerant number, chemical name.
5)trade name, refrigerant number, chemical formula, density.
1
A secondary refrigerant commonly employed in the cooling coils beneath an arena's ice surface
is
1) calcium chloride brine.
2) ammonia.
3) ammonium chloride.
4)Freon 12.
5) water.
4
The expansion (refrigerant control) valve in a refrigeration system is
1) between the compressor discharge and the compressor crankcase.
2) between the compressor and the condenser.
3) between the evaporator and the compressor.
4) between the receiver and the evaporator.
5) between the condenser and the receiver.
3
, To prevent damage due to entering liquid, reciprocating refrigeration compressors are equipped
with
1) a discharge relief valve.
2) suction line rupture discs.
3) spring-loaded safety heads.
4) a quick-closing suction valve.
5) discharge line rupture discs.
4
Actual mass = volumetric eff. x theoretical mass
= 0.75 x 8.28 kg/min
= 6.21 kg/min (Ans.)
The theoretical mass of refrigerant moved by a compressor is 8.28 kg/min. If the volumetric
efficiency is 75%, the actual mass moved is
1) 33.12 kg/min.
2) 11.04 kg/min.
3) 8.28 kg/min.
4) 6.21 kg/min.
5) 2.07 kg/min.
3
The function of the refrigeration condenser is to cool the hot compressed refrigerant
vapour until it condenses to a liquid. To do this, the condenser must remove both the heat
