Comparison of Lewis Diagrams of Ionic, Polar and Non-Polar
The best way to show and represent the unequal sharing of
electrons would be by comparison with NaCl and HCl, and H2 using
The captions below correspond to the graphic on the bottom
IONIC: Complete transfer of electrons, therefore Na
becomes positive (lost e-) and Cl becomes negative (gained e-).
POLAR: Unequal sharing. Chlorine has a greater tendency
to keep its own electron and also draw away hydrogen's electron.
It is NOT completely successful. As a result only partial charges
are established. Hydrogen becomes partially positive since it
has lost control of its electron some of the time (H +). Chlorine
becomes partially negative since it gains hydrogen's electron
some of the time (Cl -).
| In summary, a polar bond results when
different atoms share electrons. One atom will attract the bonding
electrons more strongly than the other atom and will acquire
more than a half share of these electrons. This leaves the other
atom with less than a half share and makes the electron distribution
unsymmetrical. On a time-average basis the electrons spending
more time with one atom and cause it to have a partial negative
charge. The other atom, deficient in electrons, acquires a partial
NON-POLAR: Equal Sharing. Neither atom can dominate
the other, therefore the electrons are shared equally between