With reference to refrigerating system shown in Fig. 13.1
The coefficient of performance of the refrigerator is
The coefficient of performance of a refrigerator working on Carnot cycle is
Where T1 and T2 are the highest and lowest operating temperatures in the cycle
Which of the following refrigerants is used in domestic refrigerators and in air-conditining of cinema halls?
Freon-12
Freon-22
Methyl chloride
Carbon dioxide
Suggest the material to be used for the condenser and evaporator pipes of Freon refrigeration plant
Aluminium
Brass
Copper
Stainless steel
Environmental protection agencies advise against the use of chloro-fluoro carbon refrigerants since these react with
Water vapour and cause acid rain
Plants and cause green house effect
Oxygen and cause its depletion
Ozone layer
The refrigerant used in steam jet refrigeration is
Ammonia
Freon-22
Brine
Water
The refrigerant R-22 is
Monochloro difluoro methane
Dichloro difluoro methane
Trichloro monofluoro methane
Tetra chloro difluoro methane
The refrigerant R-744 is
Rreon-12
NH3
CO2
SO2
Which of the following refrigerant has the maximum ozone depletion potential in the stratosphere?
Ammonia
Carbon dioxide
Sulphur dioxide
Fluorine
Match the refrigerant (column A) with its number (column B)
NH3-(R-40)
CO2-(R-717)
SO2-(R-744)
Methyl chloride-(R-764)
Leakage in the refrigeration system using ammonia as the refrigerant is detected by
Halide torch
Sulphur sticks
Soap and water
Burning candle
When there is leakage of ammonia refrigerant, the sulphur sticks give
Red smoke
Blue smoke
White smoke
Black smoke
Leakage of halocarbon refrigerants can be best detected by
Halide torch
Sulphur sticks
Soap and water
Burning candle
When there is leakage of Freon refrigerant, the colour of flame in halide torch test changes to
Yellow
Red
Blue
Violet
The charging of ammonia ina vapour compression system is done on
Low pressure side near the evaporator
Low pressure side near the compressor
High pressure side close to receiver
Any where in the cycle