How Do the Unique Chemical and Physical Properties of Water Make ...

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How Do the Unique Chemical and Physical Properties of Water Make Life on Earth Possible?

By | December 2007
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How do the unique chemical and physical properties of water make life on earth possible?

Heat Capacity – the amount of energy required to raise the temperature of something one degree celcius

Cohesive strength - The internal strength of the adhesive. The measure of a label's resistance to removal.

Surface Tension - the attraction of molecules to each other on a liquid's surface, creating a
barrier between the air and the liquid.

Heat of Vaporization – the amount of energy required to change a liquid to a gas

Solvent - liquid that can dissolve a substance

A physical property of water that is necessary to life on earth is the fact that ice floats. Ice is held by its hydrogen bonds in a crystal like structure in which each water molecule is bound together by 4 hydrogen bonds to other water molecules. These bonds are packed less tightly than they are in liquid water, so solid water is less dense than liquid water and therefore floats. This isn't the case in most other liquids. It's a good thing that ice floats because if it didn't then water would freeze from the bottom up. That would make it impossible for life to exist. Instead, ice forms a protective layer which keeps the water at least over zero Celsius allowing organisms to survive.

A property of water that is necessary to life on earth that is chemical is water's high heat capacity. Water's high heat capacity make it a good temperature moderator. Water's heat capacity makes oceans, ponds, lakes, and other bodies of water relatively constant throughout the seasons. It also has the effect of minimizing variations of atmospheric temperature.

Cohesive strength and surface tension are physical properties of water that make life on earth possible. Liquid water has a dynamic structure which means that hydrogen bonds are continually forming and breaking. In liquid water, each molecule forms around 3.4 hydrogen bonds which accounts for water's cohesive...