Intermolecular Forces

[pnoybballin]

Can someone please explain how to determine which compounds have a higher viscosity and Heat of Vaporization through intermolecular forces?
For an example a questions asks...

Which has the Lowest Viscosity?
C4H10 CH2F2 H20

Which has the largest Heat of Vaporization?
C2H5OC2H5 H20 C2H5OH

thank you.

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[TMP-SMX]

Can someone please explain how to determine which compounds have a higher viscosity and Heat of Vaporization through intermolecular forces?
For an example a questions asks...

Which has the Lowest Viscosity?
C4H10 CH2F2 H20

Which has the largest Heat of Vaporization?
C2H5OC2H5 H20 C2H5OH

thank you.

The more electronegative the molecule the more hydrogen bonding it will have. The more hydrogen bonding it has the more energy required to move from liquid to gas. You have to think of it in terms of how much energy has to be put into it (how stable) the molecule is.

 

[kelpy]

Water has greater viscosity since it has hydrogen bonds which are stronger than van der waals interactions found in the other two nonpolar compounds

I would say water has greater heat of vaporization, since it forms hydrogen bonds which are stronger. The intermolecular forces must be overcome for the liquid to turn into vapor. C2H5Oh also has hydrogen bonds but they should be a little weaker since the methyl group gets in the way. I hope this helps...

 

[pnoybballin]

thank you! thanks for the help you guys =D