36. Most of hydrocarbons from petroleum are obtained by

1. 1. Fractional distillation

   
   
   

   2. Fractional crystallisation

   
   
   

   3. Vaporisation

   
   
   

   4. Isomerisation

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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37. A compound containing 80% C and 20% H is likely to be

1. 1. C₆H₆

   
   
   

   2. CH₄

   
   
   

   3. C₃H₈

   
   
   

   4. C₂H₆

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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38. Assertion (A) : Large cold storage plants use ammonia as refrigerant. While domestic refrigerators use chlorofluorocarbons.
    Reason (R) : Ammonia can be liquified at ambient temperature and low pressure
    Codes

1. 1. Both A and R are true and R is the correct explanation of A

   
   
   

   2. Both A and R are true but T is not the correct explanation of A

   
   
   

   3. A is true but R is false

   
   
   

   4. A is false but R is true

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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39. The vapour density of a volatile substance is 4 (CH₄ =1). Its molecular mass would be

1. 1. 2

   
   
   

   2. 8

   
   
   

   3. 64

   
   
   

   4. 128

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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40. Pyroligneous acid contains

1. 1. 2% acetic acid

   
   
   

   2. 50% acetic acid

   
   
   

   3. 10% acetic acid

   
   
   

   4. 20% acetic acid

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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