What determines vander waal force of attraction.why it inc with size of the compound?

Dear Student,

Kindly refer to the link for similar query:

• Determination of Van der Waal's forces - https://www.meritnation.com/ask-answer/question/what-are-weak-van-der-waals-forces-of-attraction/carbon-and-its-compounds/8942291
• Reason for the increase with increase in size - 
  • Bigger Atoms are highly Polarizable.
  • Bigger Molecules have more electrons to Polarize .

Hope this information clears your doubts about the topic

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