Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Kero_1116 on October 03, 2005, 09:21:41 PM
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anyone know the polarity of alcohol, ammonium chloride, gasoline, iodine crystal, glycerol, and chloroform? i'm having difficulty with knowing if a compound is polar or non-polar
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Figure out whether it has an overall dipole moment and you'll be on your way.
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dipole movement? i do not know anything about that
i know one way of finding the electonegativity, but how to find it on the compounds i stated
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You have to draw out the structure. :)
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If you are familiar with electronegativity try looking at the difference in electronegativity in the bonds between various atoms in your molecules. If there is a large difference then the bond is usually polar. For example a bond between two carbon atoms C-C is not polar because the electronegativities at each end of the bond are the same, however in a hydrogen oxygen bond O-H the bond is polar becase the difference in electronegativities is large.
The next thing to consider is whether the molecule is symmetrical or not (can you put a mirror through the middle of the molecule). Because if the polarities of the bonds in a molecule cancel out then the molecule over all is not polar. For example CF4 has four polar C-F bonds in it, but the molecule is symmetrical so all the polarities cancel each other out to make the over all molecule non-polar.