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Chemistry explanation

anniela2000

Could someone explain why van der Waal's forces are stronger than dipole dipole in this question

(edited 6 years ago)

Reply 1

anniela2000

Original post by Annie_La

Could someone explain why van der Waal's forces are stronger than dipole dipole in this question

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Reply 2

tony_dolby

The normal answer is to say that iodomethane is bigger so it has more electrons than fluoromethane. These Van der Waals forces are strong and take more energy to break than the dipole dipole forces in fluoromethane.

A third mark might be gained by saying that larger number of electrons in iodomethane increases the Van der Waals forces and this ooutweighs the weaker dipole-dipole forces in iodomethane when compared to fluoromethane.

A strange question though and not the normal 'run of the mill' type.