281. Bond formation in dry ice (solid CO₂) is due to:

1. 1. Vander Waals force

   
   
   

   2. Electrostatic force

   
   
   

   3. Newton’s force

   
   
   

   4. Hydrogen bond

   
   
   

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1. View Hint View Answer Discuss in Forum

   Bond formation in dry ice is due to Vander Waals force.

   Correct Option: A

   Bond formation in dry ice is due to Vander Waals force.

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282. A material is most stable when its potential energy is:

1. 1. maximum

   
   
   

   2. infinite

   
   
   

   3. minimum

   
   
   

   4. zero

   
   
   

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1. View Hint View Answer Discuss in Forum

   A material is most stable when its potential energy is minimum.

   Correct Option: C

   A material is most stable when its potential energy is minimum.

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283. Bond energy of a solid is defined at:

1. 1. r > r₀

   
   
   

   2. r = r₀

   
   
   

   3. r < r₀

   
   
   

   4. r → ∞

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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284. In the above question, the potential energy at infinity will be equal to:

1. 1. ∞

   
   
   

   2. - A

      r2

   
   
   

   3. zero

   
   
   

   4. a constant finite value

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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285. If Coulomb’s attractive force is of	A
     	r2

     form in a material system, its potential energy will be given by:

1. 1. A

      r

   
   
   

   2. - A

      r

   
   
   

   3. A

      r3

   
   
   

   4. - A

      r3

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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