Monday, July 6, 2020

Topsoil, rainfall and the magic of water

Two pictures showed up on my FB news feed this past week. One is this meme which has been around several times and which as a farm boy, still at heart, I have to agree with. The depth of the topsoil may vary as does the rainfall but without them we could not grow food. Agriculture and livestock production are merely the harnessing of these along with capturing sunlight to produce crops, meat and milk.

The other picture that caught my eye was this one of a swimmer just before breaking the surface tension of water. I found a couple more to go with it. Water is an amazing substance.  It is the stuff of life itself (without water you can't make coffee or whiskey but I digress). It was considered one of the four elements: Earth, Fire, Air, and Water.




The properties of water were covered in highschool and again in Chemistry 101 but after 55 years, I had to look it up again. Encyclopaedia Britannica to the rescue (https://www.britannica.com/science/water). Water (H2O) has an atomic weight of 18 and ought to be a gas with a boiling point of -100C. However hydrogen bonding gives water in all phases some very unique properties.

Ice floats on water, it does not sink, which is different from other solids which sink as the liquid turns solid. That means life is sustained beneath the ice in rivers, ponds and lakes that do not freeze to the bottom.

Water is as close to the universal solvent as one is likely to find.
In addition, the hundreds of chemical reactions that occur every instant to keep organisms alive all take place in aqueous fluids. Also, the ability of foods to be flavoured as they are cooked is made possible by the solubility in water of such substances as sugar and salt. Although the solubility of substances in water is an extremely complex process, the interaction between the polar water molecules and the solute (i.e., the substance being dissolved) plays a major role. When an ionic solid dissolves in water, the positive ends of the water molecules are attracted to the anions, while their negative ends are attracted to the cations. This process is called hydration. The hydration of its ions tends to cause a salt to break apart (dissolve) in the water. In the dissolving process the strong forces present between the positive and negative ions of the solid are replaced by strong water-ion interactions.

At high temperature and pressure, "supercritical" water will dissolve non-polar substances such as toxic wastes so they can be destroyed safely.

Far all chemistry nerds reading this, the Britannica article is not very long and well illustrated. For the rest, raise a glass of water and toast the magic of covalent bonding on which life as we know it depends.

6 comments:

Debra She Who Seeks said...

Those surface tension photos are amazing -- especially the first one!

The Blog Fodder said...

That is what caught my eye and reminded me how amazing water really is.

JACKIESUE said...

wow, that's amazing.

The Blog Fodder said...

Isn't it though.

Ol'Buzzard said...

I am convinced that the quality of earth's water is declining. On our last stint in Alaska we were in a village on the Kuskokwim River. There was a gold mine up river, a molybdenum mine also up river and a platinum mine down river. There was a high cancer rate in the village. We distilled all our drinking water. I think what the water analysis declares as drinkable is still not healthy over a ling haul. The Ohio river has signs warning people not to eat any more than one fish meal every couple of weeks and that pregnant women should not eat fish caught in the river. Even here in pristine Maine, it is recommended not to eat a constant diet of fish caught in our waters. Man made polluting is increasing with our world population increases, and this is not good news for the quality of our water.
the Ol'Buzzard

Diane Henders said...

When I was a young kid we had no running water in our house, so I've never been able to shake the "conservation" attitude that develops when every drop has to be lugged in by bucket. Fresh, pure water is the most precious substance on earth. Even after decades of having virtually unlimited good-quality running water, I still consider it a tremendous luxury. And those photos are fabulous!