"BONDING"

Bob Hicks

"Maternal bonding," "male bonding," "epoxy bonding," ... what about "hydrogen bonding"? It describes not only the most important natural phenomenon for our buoyancy, but also for the very existence of liquid water. Without it we’d sink immediately to the bottom - on one last, quick dive before the oceans vaporized at a mere 70ºF and iced to the bottom forever at 32ºF.

H2O is a "polar molecule," held tightly together because the electron in the hydrogen atom is drawn closer to the oxygen atom, making the hydrogen side of the molecule slightly positive and the oxygen side slightly negative. Water molecules then cling to one another like opposite poles of many magnets, and they bond tighter than a herd of musk ox fending off a wolf. "Hydrogen bonding" creates the surface tension that causes water to "bead," and to hold afloat a needle of much greater density.

This tight bonding explains why water absorbs enormous quantities of heat before vaporizing. Without this peculiar polarity, the oceans would vaporize at room temperature. They would no longer maintain the Earth’s temperature within our range for species-viability.

Without "hydrogen bonding," water wouldn’t be the universal solvent for cleaning soiled articles. Water annihilates smudges only because the negative ions in the smudge are attracted to the positive hydrogen atoms of water, and the positive ions in the smudge are attracted to the negative oxygen atoms of water. (It doesn’t work with oils and fats because they are non-polar molecules and don’t emulsify in water.)

The density/temperature relationship of water is also different from most liquids. Cooling water becomes denser only to 39ºF. Then crystals form, expand, and become less dense at lower temperatures. If ice sank, new ice would be forming on the surface all winter, causing massive freezing of the earth’s oceans and lakes. Summer would be too short to thaw it.

Unique liquid, that water we dive in. Enjoy it with a new appreciation of how inhospitable Earth would be ... without "bonding."

(Frome AWDCI Newsletter 8/00)