286. The resultant force in a stressed material becomes repulsive when:

1. 1. r = r₀

   
   
   

   2. r < r₀

   
   
   

   3. r > r₀

   
   
   

   4. r >> r₀

   
   
   

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   NA

   Correct Option: B

   NA

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287. Bond length in ionic bond is of the order of:

1. 1. 1 to 2 Å

   
   
   

   2. 3 to 4 Å

   
   
   

   3. 5 to 6 Å

   
   
   

   4. 7 to 8 Å

   
   
   

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1. View Hint View Answer Discuss in Forum

   Bond length in ionic bond is of the order of 1 to 2 Å.

   Correct Option: A

   Bond length in ionic bond is of the order of 1 to 2 Å.

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288. The nature of bond is governed by the:

1. 1. Geometry of unit cell

   
   
   

   2. Electron structure of the atom

   
   
   

   3. Orientation of crystal

   
   
   

   4. Basis of filling of space lattice

   
   
   

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1. View Hint View Answer Discuss in Forum

   The nature of bond is governed by the electron structure of the atom.

   Correct Option: B

   The nature of bond is governed by the electron structure of the atom.

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289. The nature of bond is governed by the:

1. 1. Geometry of unit cell

   
   
   

   2. Electron structure of the atom

   
   
   

   3. Orientation of crystal

   
   
   

   4. Basis of filling of space lattice

   
   
   

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1. View Hint View Answer Discuss in Forum

   The nature of bond is governed by the electron structure of the atom.

   Correct Option: B

   The nature of bond is governed by the electron structure of the atom.

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290. The forces involved in the chemical bonding are:

1. 1. Pauli’s forces

   
   
   

   2. Newton’s forces

   
   
   

   3. Planck’s forces

   
   
   

   4. Coulomb’s forces

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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