21. An intensive property in thermodynamics means a property which depends

1. 1. on the amount of the substance only

   
   
   

   2. on the nature of the substance only

   
   
   

   3. both on the amount as well as nature of the substance

   
   
   

   4. neither on the amount nor on the nature

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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22. The efficiency of a heat engine is maximum when

1. 1. temperature of source is greater than that of sink

   
   
   

   2. temperature of sink is greater than that of source

   
   
   

   3. temperature difference of source and sink is minimum

   
   
   

   4. temperature difference of source and sink is maximum

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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23. Octane number of fuel can be increased by

1. 1. Isomerisaiton

   
   
   

   2. Alkylation

   
   
   

   3. Reforming

   
   
   

   4. All of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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24. The gas supplied in cylinders for cooking is

1. 1. Marsh gas

   
   
   

   2. LPG

   
   
   

   3. Mixture of CH₄ and C₂H₆

   
   
   

   4. Mixture of ethane and propane

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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25. A substance that can supply energy either along or by reacting with another substance is known as

1. 1. Rayon

   
   
   

   2. Fibres

   
   
   

   3. Fuels

   
   
   

   4. Thiokol

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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