46. Which one of the following is used as an anti-freeze for the automobile engines ?

1. 1. Propyl alcohol

   
   
   

   2. Ethanol

   
   
   

   3. Methanol

   
   
   

   4. Ethylene glycol

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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47. 'Freon' used as refrigerants is chemically

1. 1. Chlorinated hydrocarbon

   
   
   

   2. Fluorinated hydrocarbon

   
   
   

   3. Chlorofluoro hydrocarbon

   
   
   

   4. Fluorinated aromatic compound

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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48. Which of the following metals is not a pollutant ?

1. 1. Mercury

   
   
   

   2. Arsenic

   
   
   

   3. Lead

   
   
   

   4. Aluminium

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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49. Highly toxic gas which causes headache, visual difficulty, paralysis and even death is

1. 1. CO₂

   
   
   

   2. O₃

   
   
   

   3. CO.

   
   
   

   4. all of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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50. The water pollution in river is measured by the dissolved amount of

1. 1. chlorine

   
   
   

   2. ozone

   
   
   

   3. nitrogen

   
   
   

   4. oxygen

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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