2191. Which of the following statements about the physical properties of non metals is not correct ?

A. They are not ductile
B. The majority of these have high liquefying and edges of boiling over *
C. They do not conduct electricity
D. The are not malleable

2192. The difference in the physical properties of metals and non metals are due to :

A. Different structures of their atoms *
B. Different number of their atoms
C. The fact that metals have atoms whereas non metals have none
D. None of these

2193. In the laboratory preparation of chlorine manganese dioxide :

A. Function as a catalyst
B. Gets oxidised
C. Gets reduced *
D. None of these

2194. Which of the following sources meet nearly 80% of the world energy requirement ?

A. Dung and vegetation waste
B. Nuclear , solar energy , geothermal and wind power
C. Hydro power
D. Fossil fuels *

2195. Some source of energy are continuously produced in nature and are essentially inexhaustible which of the following is such a source ?

A. Coal and ignite
B. Geothermal power *
C. Natural gas and crude oil
D. Uranium

2196. Which of the following copper alloys is used for the manufacture of caps of cartridges ?

A. Brass *
B. Bronze
C. Gun metal
D. German silver

2197. Pyrheliometer is an instrument used for :

A. Looking at the radiant force of the wellspring of light
B. Measuring solar radiations *
C. Measuring heat radiations
D. Measuring heat radiations

2198. Which of the following statements about the laws of falling bodies is not correct ?

A. In vaccum, all bodies starting from rest fall with equal velocity
B. The space traversed by a body falling from rest is equal to the square of the time *
C. The velocity acquired by a body falling freely from rest is proportional to the time of its fall
D. ALL of the above

2199. The sun spectrum is :

A. Line spectrum
B. Band Spectrum *
C. Continuous spectrum
D. None of the above

2200. What is known to be the first metal discovered by man ?

A. Iron
B. Copper *
C. Bronze
D. Gold