1. Transition metals are often paramegnetic owing to

1. 1. High m.p and b.p

   
   
   

   2. The presence of vacant orbitals

   
   
   

   3. The presence of unpaired electrons

   
   
   

   4. Malleability an ductility

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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2. Which of the following pairs of atomic numbers, represent the elements belonging to the same group ?

1. 1. 15 and 13

   
   
   

   2. 12 and 21

   
   
   

   3. 14 and 31

   
   
   

   4. 13 and 31

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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3. All the elements is a group in the periodic table have the same

1. 1. Atomic weight

   
   
   

   2. Same number of valence electrons

   
   
   

   3. Atomic number

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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4. Aluminium bears a diagonal relationship with

1. 1. Beryllium

   
   
   

   2. Boron

   
   
   

   3. Carbon

   
   
   

   4. Gallium

   
   
   

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   NA

   Correct Option: A

   NA

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5. Modern periodic table is based on atomic number of the elements. The significane of atomic number was proved by the experiment of

1. 1. Moseley's work on X-ray spectra

   
   
   

   2. Bragg's work on X-ray diffraction

   
   
   

   3. Mulliken's oil drop experiment

   
   
   

   4. Discovery of X-ray by Roentgen

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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