171. The gas involved in Bhopal incident was
     

1. 1. Hydrogen sulphide
      

   
   
   

   2. Nitrogen dioxide
      

   
   
   

   3. Methyl chloride
      

   
   
   

   4. Methyl isocyanide

   
   
   

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1. View Hint View Answer Discuss in Forum

   Methyl Isocyanide gas.

   Correct Option: D

   Methyl Isocyanide gas.

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172. Charcoal is used in water treatment as a/an
     

1. 1. absorbent
      

   
   
   

   2. coagulant
      

   
   
   

   3. solvent
      

   
   
   

   4. adsorbent

   
   
   

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1. View Hint View Answer Discuss in Forum

   Charcoal is used in water treatment as adsorbent.

   Correct Option: D

   Charcoal is used in water treatment as adsorbent.

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173. Philosopher’s wool is chemically
     

1. 1. Aluminium oxide
      

   
   
   

   2. Magnesium oxide
      

   
   
   

   3. Zinc oxide
      

   
   
   

   4. Calcium oxide

   
   
   

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1. View Hint View Answer Discuss in Forum

   Philosopher’s Wool is chemically zinc oxide.

   Correct Option: C

   Philosopher’s Wool is chemically zinc oxide.

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174. Sodium vapour lamps glow with yellow colour. This is due to
     

1. 1. sublimation of sodium to emit yellow colour

   
   
   

   2. the emission of excess energy absorbed by sodium atoms, in the yellow region of the spectrum

   
   
   

   3. the low ionisation energy of sodium
      

   
   
   

   4. its ability to absorb all other colours except yellow

   
   
   

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1. View Hint View Answer Discuss in Forum

   Sodium Vapour Lamps glow with yellow colour due to the emission of excess energy absorbed by sodium atoms, in the yellow region of the spectrum.

   Correct Option: B

   Sodium Vapour Lamps glow with yellow colour due to the emission of excess energy absorbed by sodium atoms, in the yellow region of the spectrum.

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175. Which of the following is used as a moderator in nuclear reactors ?
     

1. 1. Thorium
      

   
   
   

   2. Graphite
      

   
   
   

   3. Ordinary water
      

   
   
   

   4. Radium

   
   
   

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1. View Hint View Answer Discuss in Forum

   Graphite is used a moderator in nuclear reactors.
   

   Correct Option: B

   Graphite is used a moderator in nuclear reactors.
   

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