Question

The vanderwaals radii of O,N,cl,F and Ne increases in the order ?

Answer 1

Van der waals radius is defined as half of the distance between the nuclei of the two non bonded neighbouring atoms of two adjacent molecules in solid state. Van der waal radius decreases from going left to right in a periodic table as the effective nuclear charge increases and increases on going from top to bottom along a group as more shells are added and effective nuclear charge decreases.
So, the increasing order of Van der waal radius is:
F(147 pm)<O(152 pm)<Ne(154 pm)<N(155 pm)<Cl(175 pm)
​It is observed that Ne has greater Van der waal radius than F and O despite being in the last group. This is because Ne gas in the solid state are linked together by weak intermolecular forces i.e. Van der waal forces while the atoms of other gases are held together by strong forces that is chemical bonds. Consequently, the radius of Ne atoms are larger.

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