Chemistry

chemistry based questions
DIRECTIONS : Questions based on Chemistry.
36. Which one of the following is present in the emission from "unleaded petrol"?
  A.  carbon monoxide
  B.  carbon dioxide
  C.  ethylene
  D.  hydrocarbons
37. Which one of the following is used in preparing match sticks?
  A.  Chile saltpeter
  B.  Indian salpetre
  C.  Red phosphorus
  D.  Sodium bicarbonate

38. Chloro-fluro-carbon gases are not used in which of the following?
  A.  aerosol sprays
  B.  fire-extinguishers
  C.  refrigerators
  D.  air-conditioning
39. Among the following elements, which one is not present in a pure sugar?
  A.  Carbon
  B.  hydrogen
  C.  Nitrogen
  D.  oxygen
40. Which one of the following has the highest fuel value?
  A.  hydrogen
  B.  charcoal
  C.  natural gas
  D.  gasoline