16. The electronic configuration of an iron atom is:

1. 1. 1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁶, 4s²

   
   
   

   2. 1s², 2s², 2p⁶, 3s², 3p⁶, 3d³, 4s²

   
   
   

   3. 1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁸, 4s²

   
   
   

   4. None of the above

   
   
   

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   NA

   Correct Option: A

   NA

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17. The Miller indices of the diagonal plane of a cube are:

1. 1. 110

   
   
   

   2. 111

   
   
   

   3. 100

   
   
   

   4. 000

   
   
   

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   NA

   Correct Option: A

   NA

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18. The crystal structure of most of the common metals is:

1. 1. hexagonal

   
   
   

   2. cubic

   
   
   

   3. orthorhombic

   
   
   

   4. None of these

   
   
   

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   The crystal structure of most of the common metals is cubic.

   Correct Option: B

   The crystal structure of most of the common metals is cubic.

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19. The nature of atomic bond found in diamond is:

1. 1. ionic

   
   
   

   2. covalent

   
   
   

   3. metallic

   
   
   

   4. None of these

   
   
   

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   The nature of atomic bond found in diamond is covalent.

   Correct Option: B

   The nature of atomic bond found in diamond is covalent.

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20. Insulating materials that can withstand a temperature above 180°C is of:

1. 1. class A type

   
   
   

   2. class B type

   
   
   

   3. class C type

   
   
   

   4. class H type

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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