294. Heavy water is so called because it [Asstt Commdt 2011]
     (a) contains a number of salts as in sea water
     (b) is the mercury contaminated water
     (c) is saline water used in hospitals
     (d) contains the heavier isotope of hydrogen in water
Ans: (d)
295. Which one among the following statements is correct? [Asstt Commdt 2011]
     (a) Melting of ice and burning of candle represent the same kind of chemical change
     (b) Melting of ice is a physical change and burning of candle is a chemical change
     (c) Melting of ice is a chemical change and burning of candle is a physical change
     (d) Melting of ice and burning of candle represent the same kind of physical change
Ans: (b)
296. Steam at 100°C is more effective in heating than water at the same temperature because [Asstt Commdt 2011]
     (a) steam is in the gaseous state and water is in the liquid state
     (b) steam has an additional heat known as "latent heat of vaporization"
     (c) water has hydrogen bonds but steam does not
     (d) transfer of heat from steam is easier than water
Ans: (b)
297. Match the following: [Asstt Commdt 2011]
     A. Iron oxide            1. Glossy finish on wood and steel
     B. Varnish               2. Colour less shining protective coating on wood
     C. Enamel paint          3. Exterior and interior brick walls
     D. Emulsion paint        4. Preparatory coaling on steel
          A         B         C         D
     (a)  4         1         2         3
     (b)  3         1         2         4
     (c)  4         2         1         3
     (d)  3         2         1         4
Ans: (c)
298. The name of the particle "Boson" is associated with the name of [Asstt Commdt 2011]
     (a) J.C Bose
     (b) S. N. Bose
     (c) Isaac Newton
     (d) Albert Einstein
Ans: (b)
299. Uranium eventually decays into a stable isotope of [CPO SI 2011]
     (a) Radium
     (b) Thorium
     (c) Lead
     (d) Polonium
Ans: (c)
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