The substance used as a smoke screen in warfare is

A. C2H2

B. SiCl4

C. P2O5

D. PCl5

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

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  1. Which of the following is the most suitable abrasive for grinding high tensile strength materials?
  2. Ferromagnetic materials owe their properties to __________ inner sub-shells.
  3. Property responsible for the talcum powder to cling to the skin is the
  4. Which of the following is not a characteristic observed in material failure by fatigue fracture?
  5. The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________…
  6. __________ property of a material is determined by the Herbert Pendulum device.
  7. Case hardening is not done by
  8. Which of the following is the correct nature of shear stress distribution along the cross section in…
  9. Liquor poisoning generally occurs due to the presence of __________ in it.
  10. The dew point temperature lines on psychrometric charts are straight inclined sloping downwards to the…
  11. A material in which the atoms are arranged regularly in some directions but not in others, is termed…
  12. Consideration of the creep is the most important in case of the
  13. Pick out the wrong statement.
  14. Which of the following is preferred for riveting?
  15. Wrought iron is not
  16. Which one can be directly solidified from gaseous state without entering into liquid state?
  17. The following type of bonding is strongly directional in solids.
  18. Difference at any instant between the value of the controlled variable and the set point is called the
  19. __________ is the hardest oxide and is hence used where high wear resistance at high temperature is…
  20. Exposure to __________ accelerates the degradation of plastics.
  21. Hot extrusion process is not used for making
  22. Working of linear variable differential transducer (LVDT) is based on the principle of variable
  23. Stainless steel is welded with difficulty because of
  24. The most detrimental impurity in high pressure boiler feed water is
  25. Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect…
  26. Increasing sulphur content in pig iron tends to make it
  27. With increase in temperature, the surface tension of water
  28. The bank of tubes located at the back of the domestic refrigerators are the __________ tubes.
  29. In a furnace with heating element temperature at 1700°C, the dominant mechanism of heat transfer…
  30. The joint for soldering is supported by binding wire made of