21. Which one of the following electrolytes on passing electricity ?

1. 1. Ethanol

   
   
   

   2. Propanone

   
   
   

   3. Lunar caustic

   
   
   

   4. Starch

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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22. Which of the following cell is a secondary cell ?

1. 1. Dry cell

   
   
   

   2. Mercury cell

   
   
   

   3. Fuel cell

   
   
   

   4. Ni cell

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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23. The source of electrical energy on the Appolo moon flights was

1. 1. A generator set

   
   
   

   2. Fuel cell

   
   
   

   3. Ni-Cd Cell

   
   
   

   4. Leas storage batteries

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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24. When a lead storage battery is charged, it acts as

1. 1. A primary cell

   
   
   

   2. A galvanic cell

   
   
   

   3. A conentration cell

   
   
   

   4. An electrolytic cell

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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25. A conductivity cell is platinised

1. 1. to prolong its service

   
   
   

   2. to avoid temperature effect

   
   
   

   3. to avoid plarization effect

   
   
   

   4. none of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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