The Polarity of Bonding and Van der Waals Force

Rucete ✏ Chemistry In a Nutshell

The Polarity of Bonding

1 Polar bonds

1 If electrons are not shared equally between the molecules, the difference in electronegativity is large enough.

2 Have a positive and negative ends(or poles)

3 Dipole moment : often present in a polar molecule

2 Nonpolar bonds

  It is not pull electrons if the difference between the two atoms' electronegativity is small enough.

3 Dipole moment

1 Represent molecule's polarity by measuring dipole moment.

2 If dipole moment is high much, most of them are polar molecule.

3 The more it has electrical charge and the longer the distance between the charges, the more they have big value.

Van der Waals Force

1 Dipole-dipole, Dipole-induced dipole, Dispersion force

2 Dispersion force exist whether it is polar or nonpolar.

 1. The larger the molecular weight and the wider the surface area, the greater the dispersion.

 2. On average, the valence electron that has large molecular weight and wide surface area is likely to       be far away from nuclear, and make easily and temporarily dipole by weakly dispersion force.

 3. Electron placed around atom or molecule can be easily polar.