11. Structure of solids investigated by using

1. 1. cosmic rays

   
   
   

   2. Z - rays

   
   
   

   3. infrared

   
   
   

   4. y - rays

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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12. The nitrogen atom has 7 protons and 7 electrons. The nitride ion will have

1. 1. 10 protons and 7 electrons

   
   
   

   2. 7 protons and 10 electrons

   
   
   

   3. 4 protons and 7 electrons

   
   
   

   4. 4 protons and 10 electrons

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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13. Positive ions are formed from neutral atoms by loss of

1. 1. neutrons

   
   
   

   2. protons

   
   
   

   3. nuclear charge

   
   
   

   4. electrons

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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14. The value of Planck's constant is

1. 1. 6.62 x 10^-34 J

   
   
   

   2. 6.62 x 10^-34 J.s

   
   
   

   3. 6.62 x 10^-34 erg.s

   
   
   

   4. none of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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15. The nucleus of a singly ionized carbon atom contains

1. 1. 6 protons and 6 neutrons

   
   
   

   2. 5 protons and 6 neutrons

   
   
   

   3. 6 protons and 6 neutrons and 6 electrons

   
   
   

   4. 12 protons and 6 neutrons and 6 electrons

   
   
   

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1. View Hint View Answer Discuss in Forum

   The charged carbon atom in a carbocation is a "sextet", i.e. it has only six electrons in its outer valence shell instead of the eight valence electrons that ensures maximum stability (octet rule). Therefore carbocations are often reactive, seeking to fill the octet of valence electrons as well as regain a neutral charge.
   

   Correct Option: A

   The charged carbon atom in a carbocation is a "sextet", i.e. it has only six electrons in its outer valence shell instead of the eight valence electrons that ensures maximum stability (octet rule). Therefore carbocations are often reactive, seeking to fill the octet of valence electrons as well as regain a neutral charge.
   

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