66. The electronic cofiguration of Gu is

1. 1. 3d⁹ 4s²

   
   
   

   2. 3d¹⁰ 4s¹

   
   
   

   3. 3d⁹ 5s²

   
   
   

   4. 3d¹⁰ 5s¹

   
   
   

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   NA

   Correct Option: B

   NA

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67. An alloy is

1. 1. Intermetallic compound

   
   
   

   2. A solid substance containing two or more metallic elements

   
   
   

   3. A solid which contains one non-mental

   
   
   

   4. A solid which contains more than one non-metal

   
   
   

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   NA

   Correct Option: B

   NA

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68. The process of sudden cooling is known as

1. 1. annealing

   
   
   

   2. diffusion

   
   
   

   3. quencing

   
   
   

   4. sedimentation

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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69. Which of the following cannot form peroxides and superoxides ?

1. 1. Na

   
   
   

   2. Li

   
   
   

   3. K

   
   
   

   4. Rb

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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70. Which of the following is a carbonate ore ?

1. 1. cassiterite

   
   
   

   2. pyrolysite

   
   
   

   3. diaspore

   
   
   

   4. malachite

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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