Electron Dot Formulas

Here are some examples for drawing electron dot formulas. You should be able to draw the electron dot formulas for NaCl, for those who want more knowledge, you can check out the formulas for nitrogen, methanol, and for the bicarbonate ion.

Octet rule

Usually all molecules follow the octet rule, and have a total of 8 electrons in bonds or as lone pairs. Some examples of octect rule violators were given in class: nitric oxide, nitrogen dioxide, hydroxyl radical, and super oxide. Electron dot diagrams for these violators are here.

Radicals

Radicals are produced in the body from both beneficial processes and detrimental processes. Macrophages are defense cells, they protect the body from harmful invaders (virons and bacteria) by engulfing the invaders. Macrophages make superoxide and this is converted to hydrogen peroxide. Hydrogen peroxide can then form hydroxyl radicals. Macrophages use these hydroxyl radicals to destroy the components of the invaders that they have ingested.

Hydroxyl radicals are also produced from a process called lipid peroxidation. Lipids are fats. The lipids end up in the blood stream and are peroxidized (oxygen is added to them). These peroxidized lipids then decompose to form hydroxyl radicals. These hydroxyl radicals then cause tissue dammage. High fat diets are associated with an increased in risk of colo-rectal cancer, and this lipid peroxidation mechanism may be involved.

Polar molecules

Polar molecules result when there is unequal sharing of a bond pair of electrons. Unequal sharing results from a difference in electronegativity. A more electronegative atom will pull the electron pair away from the other atom. Often shrieking, "Mine, all mine!". Electronegative atoms are electron hogs! The more unequal the sharing, the more polar the bond. Flourine is the most electronegative element, oxygen and nitrogen are also very electronegative.

The O-H bond in water is polar because oxygen is more electronegative than hydrogen. The C-H bond in methane is not polar, because there is a very tiny difference in electronegativity between C and H.

Hydrogen bonding

Molecules that have hydrogen bonded to F, O, or N can form special intermolecular bonds called Hydrogen bonds. Both molecules on either side of the hydrogen bond must have either a N, an O, or an F. (Have we had NOF FON yet?) Water is a very important example of hydrogen bonding.

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Copyright 1995 Koni Stone