46. Which law of thermodynamics introduces the concept of entropy ?

1. 1. First law

   
   
   

   2. Zeroth law

   
   
   

   3. Third law

   
   
   

   4. Second law

   
   
   

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   NA

   Correct Option: D

   NA

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47. For which one of the following elements, the standard enthalpy is not zero ?

1. 1. C (Diamond)

   
   
   

   2. C (Graphic)

   
   
   

   3. Liquid mercury

   
   
   

   4. Rhombic sulpur

   
   
   

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   NA

   Correct Option: A

   NA

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48. Vibrational energy can be said as

1. 1. only potential

   
   
   

   2. only kinetic

   
   
   

   3. (a) & (b) both partially

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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49. Which one of the following fuels causes minimum environmental pollution ?

1. 1. Diesel

   
   
   

   2. Coal

   
   
   

   3. Hydrogen

   
   
   

   4. Kerosen

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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50. Which one of the following has the highest fuel value ?

1. 1. Hydrogen

   
   
   

   2. Charcoal

   
   
   

   3. Natural gas

   
   
   

   4. Gasoline

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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