A little help on Intermolecular Forces?????

Question

I think I did this right, but I'm not sure:

HF It's shape would be Linear and it's non-polar, its IFM is Hydrogen Bond.

CO2 It's shape is Linear, it's polar and its IFM is Dipole-Dipole.

Answer 1

Yes, HF is linear, but it is not non-polar. That's because the electronegativity difference between hydrogen and fluorine is very high (4 for fluorine while 2 for hydrogen). It is in fact one of the strongest covalent polar bonds around. Since hydrogen is involved, there is hydrogen bonding involved. Y'r right there.

CO2 is linear, and slightly polar. Since it is slightly polar( electronegative values of 2.55 for C and3.44 for O respectively), we can't say that there are dipole-dipole interactions (dipoles themselves are formed when there is an appreciable degree of polarity). Therefore, the only intermolecular forces that can exist there are weak van der Waals interactions like London forces.

Answer 2

Hydrogen bond only exists on H bonded on O, N, F molecules...
its shape would be linear, but the electronegativity difference causes it to produce a dipole moment... dipole moment is the sum of all the direction of the electronegativity difference...

on CO2, the shape is linear, but there is no dipole dipole moment so thats why its non-polar so the dominant force that exist on it is dispersion force or london force


just remember, a molecule is polar if there are:
A. different attached atoms( there are more than 3 different atoms)
B. there are lone pairs in its lewis structure
C. there is a dipole moment...


if a polar molecule has no h-bond on it, then it has a dipole-dipole force..
If its a non-polar molecule, then it has a dispersion force.

thats all that i can say...

Answer 3

HF is correct

CO2 has polar bonds, but since it is linear, those polarities cancel each other out. So, the whole molecule is nonpolar and the IFM would be London Dispersion Forces

Answer 4

H-F is the strongest bond of all,,,,,,,,,,, becoz the difference between negativity of hydrogen and fluorine is 2.0 ,,,,,,,, and more the difference between electronegavity ,,,,, stronger the bond,,,,,

hence intermolecular force of attraction is more in HF molecule,,,,

but CO2 molecule is linear molecule with C-O double bond