56. Water is a good solvent of ionic salts because
.
A. it has a high specific heat
B. it has no colour
C. it has a high dipole moment
D. it has a high boiling point
57. Which of the following is not an isotope of hydrogen?
A. Tritium
B. Deuterium
C. Protium
D. Yttrium
58. The main constituents of pearls are
A. calcium oxide and ammonium chloride
B. calcium carbonate and magnesium carbonate
C. aragonite and conchiolin
D. ammonium sulphate and sodium carbonate
59. Amalgams are
A. highly coloured alloys
B. alloys which contain mercury as one of the contents
C. alloys which have great resistance to abrasion
D. alloys which contain carbon
60. Which of the following is the lightest metal?
A. Mercury
B. Lithium
C. Lead
D. Silver