Chemical Water Properties

In scientific terms, water hardness is generally the amount of dissolved calcium and magnesium in water. But in layman's terms, you may notice water hardness when your hands still feel slimy after washing with soap and water, or when your drinking glasses at home become less than crystal clear. Learn a lot more about water hardness on the Water Science School site.

We need to take the statement "Water is the universal solvent" with a grain of salt (pun intended). Of course it cannot dissolve everything, but it does dissolve more substances than any other liquid, so the term fits pretty well. Water's solvent properties affect all life on Earth, so water is universally important to all of us.

Yes, of course the most obvious fact about water is that it is wet, at least in the liquid state. But, there are many more facts about water that make it a most fascinating substance, one that all life on and in the Earth depends on.

Dissolved oxygen (DO) is a measure of how much oxygen is dissolved in the water - the amount of oxygen available to living aquatic organisms. The amount of dissolved oxygen in a stream or lake can tell us a lot about its water quality.

You don't often think that water bodies contain oxygen, but water does contain a small amount of dissolved oxygen. A small amount, but it is essential for life in the water. Biochemical oxygen demand (BOD) generally represents how much oxygen is needed to break down organic matter in water.

Nutrients, such as nitrogen and phosphorus, are essential for plant and animal growth and nourishment, but the overabundance of certain nutrients in water can cause several adverse health and ecological effects.