A common disinfectant used in village wells for disinfection of water is

A. Free chlorine

B. Bromine

C. Iodine

D. Potassium permanganate

Please do not use chat terms. Example: avoid using "grt" instead of "great".

You can do it
  1. A reduction in thermal resistance during heat transfer does not occur in the
  2. Filler material used in welding should have __________ as compared to the parent metal to be welded.
  3. Case hardening of a material is
  4. Factor of safety is the ratio of the __________ stress to the working stress.
  5. For preparation of porous bearings by powder metallurgy, preferred particle shape is
  6. In the formation of cermets, the ratio of ceramic material to metallic material is usually 80:20. Which…
  7. What happens, when SO2 is passed through a solution of H2S in water?
  8. Large scale fire on fuel gas line is normally extinguished by
  9. The most detrimental impurity in high pressure boiler feed water is
  10. Transformation range for ferrous material is the temperature interval during which __________ is formed…
  11. The rolling process cannot be used to produce
  12. Diamagnetic materials
  13. An abrupt and sudden fall in the reading of barometer is an indication of the
  14. Preheating before welding is done to
  15. With increase in compression ratio, the volumetric efficiency of air compressor
  16. Biological shield in a nuclear reactor is generally provided to protect against the
  17. A solution which resists change in its pH value on addition of acid/alkali is called the __________…
  18. A material is capable of resisting softening at high temperature, because of its property termed as
  19. Lap joints are preferred over butt joints in soldering/brazing, because these joints are
  20. Metal cutting by oxy-acetylene flame is accomplished by the __________ of the metal.
  21. Alcohols are not suitable as diesel engine fuel because the cetane number of alcohols is
  22. A gas which is collected over water becomes moistened due to water vapor, exerts its own partial pressure…
  23. Which of the following is an acidic constituent of B.F. slag?
  24. Which one of the following is incombustible?
  25. Increasing sulphur content in pig iron tends to make it
  26. Corrosion is
  27. Which of the following material handling equipments is not suitable for moving materials in varying…
  28. Which of the following is the most wear resistant grade of carbide used for the cutting tools?
  29. Uniform ramming of sand in green sand moulding process leads to
  30. Highest cutting speed is achieved by the __________ tool material.