Question : Silver gets corroded due to_________in air.

Option 1: oxygen

Option 2: Hydrogen sulphide

Option 3: Carbon dioxide

Option 4: Nitrogen

Question : In two types of brass, the ratios of copper to zinc are 8 : 3 and 15 : 7, respectively. If the two types of brass are melted and mixed in the ratio 5 : 2, a new type of brass is obtained. The ratio of copper to zinc in this new type of brass is:

Option 1: 3 : 2

Option 2: 2 : 3

Option 3: 3 : 4

Option 4: 5 : 2

Question : Blood does not coagulate inside the body due to the presence of

Option 1: Plasma

Option 2: Haemoglobin

Option 3: Heparin

Option 4: Fibrin

Question : Water flows off the wings of birds and insects due- to the presence of

Option 1: Waxes

Option 2: Sugars

Option 3: Proteins

Option 4: Minerals

Question : The major constituent of air is

Option 1: Nitrogen

Option 2: Carbon dioxide

Option 3: Oxygen

Option 4: Hydrogen