posted by ? on .
I have answered this as best as I can please can you check and help me with the ones I don't have a clue about? Thank you
Which of the moelcules listed below possesses a permanent dipole? Think about the shape of the molecule and look at the electronegatvity values...
a) CO2 - Yes (although I'm not sure)
b)CHCl3 - Yes
c)C6H12 - No
d)CH3OH - Yes
e)(CH3)2CO - Yes
f)Benzene - No
g) (Z) - 1,2 difluroethene - I have no idea, please help and explain also if you can find a diagram of the shape of the molecule it would be greatly appreciated!!!
h) (E) 1,2 difluorethene (same as above please!)
i) 1,2 dichlorobenzen - Yes but if it's wrong can you do the same as above please
j)1,4 dichlorobenzene - Yes but if it's wrong too can you again do the same as above please
CO2 is a linear molecule and although EACH O=C bond is a dipole, in the linear molecule they cancel each other because of the configuration. O=C=O
b-f inclusive are ok.
i. 1,2-dichlorobenzene is correct. I was able to find a link for that and the next one.
j. 1,4-cichlorobenzene is not a dipole and the same link will show that and why. http://g.web.umkc.edu/gounevt/Weblec211Silb/L36%2810.3-10.4%29.pdf
g) and h) Z-difluoroethene is the same as cis-difluoroethene. The Z stands for the German "zusammen" which means on the same side (same meaning as cis). I can't find a diagram on the web but the double bond means that the H-C=C-H with two Cl atoms on the same side (say at the top) are trigonal planar. With both Cl atoms on the same side it will be polar (dipole moment). With both Cl atms on the opposite side (E stands for the German "entgegen" and that means opposite (same as trans). The trans, having Cl atoms on opposite sides cancel any dipole moment and it is not a permanent dipole. IUPAC recommends naming everything with the E/Z system and not the cis/trans system.
Thank you so much! I really appreciate the help :)