General Knowledge :: General Science

The average salinity of sea water is   A. 3% B. 3.5% C. 2.5% D. 2% In which of the following activities silicon carbide is used?   A. Making cement and glass B. Disinfecting water of ponds C. cutting very hard substances D. Making casts for statues The property of a substance to absorb moisture from the air on exposure is called   A. osmosis B. deliquescence C. efflorescence D. desiccation The gases used in different types of welding would include   A. oxygen and hydrogen B. oxygen, hydrogen, acetylene and nitrogen C. oxygen, acetylene and argon D. oxygen and acetylene The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is   A. Argon B. Xenon C. Helium D. Krypton Which of the following is used as a lubricant?   A. Graphite B. Silica C. Iron Oxide D. Diamond Tetraethyl lead is used as   A. pain killer B. fire extinguisher C. mosquito repellent D. petrol additive The variety of coal in which the deposit contains recognisable traces of the original plant material is   A. bitumen B. anthracite C. lignite D. peat The hardest substance available on earth is   A. Gold B. Iron C. Diamond D. Platinum Bromine is a

A. black solid B. red liquid C. colourless gas D. highly inflammable gas