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7th Edition 3F.15

Posted: Fri Nov 30, 2018 10:22 am
by Saima Salam 3J
The problem asks us to explain the difference in the boiling points between ASF3 and ASF5 but the solution manual states that ASF3 is a polar molecule and ASF5 is a nonpolar molecule. Why is it that they are different in polarity characteristics when they are the same atom but different amount?

Re: 7th Edition 3F.15

Posted: Fri Nov 30, 2018 11:25 am
by Layal Suboh 1I
AsF3 is polar because it has a lone pair, so the dipoles do not completely cancel. All the dipoles in AsF5 cancel, that's why it is non polar. Because AsF3 is polar, it has dipole-dipole intermolecular forces, so its boiling point would be higher.

Hope this helps!

Re: 7th Edition 3F.15

Posted: Fri Nov 30, 2018 11:28 am
by anishathomas
The dipole moments in AsF5 cancel out whereas there is a lone pair in AsF3 creating polarity. Higher polarity and more imf due to this would create a higher boiling point.