Chemistry

chemistry based questions
DIRECTIONS : Questions based on Chemistry.
11. Which one of the following glasses is used in bullet proof screens?
  A.  Soda glass
  B.  Pyrex glasss
  C.  Jena glass
  D.  Reinforced glass
12. For Which one of the following is the density maximum ?
  A. Chloroform
  B. Water
  C. Benzene
  D. Ice

13. Which substance is used to retard the setting action of cement?
  A.  CaO
  B.  AlO
  C.  CaSO.2HO
  D.  NaO + KO
14. What is a mixture of potassium nitrate , powdered charcoal and sulphur called?
  A.  Glass
  B.  Cement
  C.  Paint
  D.  Gun Powder
15. Which one of the following is the softest?
  A.  Iron
  B.  Aluminium
  C.  Calcium
  D.  Lithium