Question

Question 2.23:

Suggest the most important type of intermolecular attractive interaction in the following pairs.

(i)n-hexane and n-octane

(ii)I₂and CCl₄

(iii)NaClO₄and water

(iv)methanol and acetone

(v)acetonitrile (CH₃CN) and acetone (C₃H₆O).

Answer:

(i) Van der Walls forces of attraction.

(ii) Van der Walls forces of attraction.

(iii) Ion-diople interaction.

(iv) Dipole-dipole interaction.

(v) Dipole-dipole interaction.

how will i know if it is van der waals force?

Answer 1

Van der waal force of attraction exist between non-polar molecules.
1) n-hexane and n-octane both are non-polar hence Van der Walls forces of attraction.
2) I₂ and CCl₄ both are non polar hence Van der Walls forces of attraction.
3) NaClO₄ is an ionic compound and water is a polar compound hence Ion-diople interaction
4) Methanol and acetone both are polar in nature hence Dipole-dipole interaction
5) acetone and acetonitrile both are polar in nature hence Dipole-dipole interaction