Hydrogen bond between tetrafluoromethane and water

AI Thread Summary
Tetrafluoromethane (CF4) is considered nearly insoluble in water despite the polar nature of its C-F bonds, which are more polar than O-H bonds. The discussion highlights that hydrogen bonding typically occurs between polar molecules, yet CF4 is classified as non-polar overall. The significant electronegativity difference between fluorine and carbon does not compensate for the molecule's non-polar characteristics. Consequently, the expected hydrogen bonds between tetrafluoromethane and water do not form effectively. This explains the observed low solubility of tetrafluoromethane in water at room temperature.
davon806
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Homework Statement


My textbook wrote that haloalkanes are generally insoluble in water.It is because the polar
C-X bonds are not polar enough to make the haloalkanes soluble in water.

Consider tetrafluoromethane
Difference in electronegativity between F and C = 4.0 - 2.5 = 1.5
Difference in electronegativity between O and H = 3.5 - 2.1 = 1.4
Difference in electronegativity between F and H = 4.0 - 2.1 = 1.9

So C-F bond is more polar than O-H bond in water,and much more polar than F-H bond
Therefore hydrogen bonds should form between a F atom in tetrafluoromethane and a H atom in a water molecule.

However,according to the data provided in wikipedia,tetrafluoromethane is nearly insoluble in water at r.t.p.,can anyone explain?

Thx

Homework Equations


The Attempt at a Solution

 
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Hydrogen Bond is a special case of a dipole-dipole attraction. It works between polar molecules. The group participating in H-Bonding must hence be polar. And obviously Tetrafluoromethane is non-polar.
 
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