286. Which of the following gases changes lime water in milky colour ?

1. 1. Carbon monoxide

   
   
   

   2. Nitrogen dioxide

   
   
   

   3. Hydrogen sulphide

   
   
   

   4. Carbon dioxide

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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287. Water gas is mixture of

1. 1. CO₂ and H₂O

   
   
   

   2. CO and H₂

   
   
   

   3. CO, H₂ and N₂

   
   
   

   4. CO and N₂

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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288. Which one of the following removes temporary hardness of water ?

1. 1. Slaked lime

   
   
   

   2. Hydrolith

   
   
   

   3. Plaster of paris

   
   
   

   4. Cuprous

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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289. The formula of sodium zeolite which is used in permutit process for softening water is

1. 1. Na₂OAI₂O₃Si₂O xH₂O

   
   
   

   2. Na₂OAI₂O₃SiO₄ xH₂O

   
   
   

   3. K₂AI₂SiO₈ xH₂O

   
   
   

   4. Na₂AI₂Si₂O₄ xH₂O

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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290. Which of the following glasses is used in making wind screen of automobiles

1. 1. Pyrex

   
   
   

   2. Jena

   
   
   

   3. Crook's

   
   
   

   4. Safety

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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