1. The gas which is a working substance in a refrigerating system is called the ————————-.
  2. Refrigerant is used for producing———————in the evaporator.
  3.  Chemical formula for R-22 is———————————.
  4.  Gas which serves as a medium of transferring heat from one place to ——is called refrigerant.
  5. Ammonia boils at —— and freezes at———-at atmospheric pressure.
  6.  Latent heat of ammonia is —————-.
  7. Ammonia is not corrosive to ———————-.
  8. The chemical formula of R-134 a is —————–.
  9. Normal boiling point of R-22 is—————–.
  10. Boiling point of R-134 a is ————-.
  11.  Practical use of carbon dioxide in refrigeration is in the form of ——————-.
  12. In a Freon gas the hydrogen atoms are replaced by——————– and—————-.
  13. Name the compound of R-22—————————-.
  14. Spells the compound of R 134 a————————–.
  15. Usually a solution of ————— and salt is called a brine solution.
  16. Most common salts used for making brine solution are sodium chloride and——————.
  17. Brine solution is used for making ice and———————–.
  18. Freezing point of calcium chloride is——————–.
  19. Common method of locating the leakage of refrigerant is by using—————.
  20. Leakage should be tested when the cooling plant is at——————.
  21.  Freon refrigerant leakage is found by using —————.
  22.  Latent heat of water is——————–
  23. Ammonia is highly corrosive to————–..
  24. Generally —–gas is used for flushing the refrigeration system and also for testing the leakage.
  25. Liquid refrigerant at low pressure ————–quickly in the evaporator..


ANS: 1.Refrigerant,2. Cooling, 3. CH Cl F2, 4.Another, 5.—33.5 C and –78 C, 6.1371 k J/kg, 7. mild steel, 8. C2H2F4, 9.—41C, 10. –27 C, 11.Dry ice, 12.Chlorine and Fluorine, 13. Mono-chloro-difluoro-methane, 14. Tetra fluoro ethane, 15.Water, 16. Calcium chloride, 17.Ice-cream, 18.  –46 C, 19. Soap solution, 20. Rest, 21. Halide torch, 22. 2257 k J/kg, 23.Copper, 24. Carbon dioxide, 25. Evaporates. .