Chemistry

DIRECTIONS : Questions based on Chemistry.
46. | What are Rubies and Sapphires chemically known as | ||
---|---|---|---|
A. silicon dioxide | |||
B. aluminium oxide | |||
C. lead tetra oxide | |||
D. boron nitride |
47. | Acid rain contains high levels of | ||
---|---|---|---|
A. oxalic acid | |||
B. acetic acid | |||
C. sulphuric and nitric acids | |||
D. carbolic acid |
48. | Talc contains which one of the following ? | ||
---|---|---|---|
A. zinc,calcium,oxygen | |||
B. calcium,oxygen,tin | |||
C. magnesium,silicon,oxygen | |||
D. zinc,tin,sulphur |
49. | Which one of the following substances is made up of only one type of atoms? | ||
---|---|---|---|
A. water | |||
B. hydrogen | |||
C. milk | |||
D. air |
50. | Which one of the following is used as a mordant in dyeing and tanning indusrty? | ||
---|---|---|---|
A. Magnesium oxide | |||
B. magnesium carbonate | |||
C. magnesium chloride | |||
D. magnesium sulphate |