The Chemistry of Water

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"The Chemistry of Water"
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Water is essential to life. Water's chemistry is unique and essential to life functioning the way it does. If water did not have the chemical properties it has, then life as we know it would not exist.

At first glance, water's chemistry seems relatively simple. It is only comprised of an oxygen atom and 2 hydrogen atoms which are joined together by covalent bonds. But oxygen is not a nice atom, it is what is called an electron hungry atom. That means it attracts the electrons that are shared between it and the hydrogen atoms. The electrons, therefore, spend more time around the oxygen atom then they do the hydrogen atoms. This gives the oxygen a partially negative charge and the hydrogen atoms have a partially positive charge. These partial charges cause there to be weak attractions called hydrogen bonds between the molecules of water.

This hydrogen bonding is responsible for the "life" giving properties of water which include the cohesion property of water, the temperature moderating property of water, ice's ability to float on water, and water as a solvent.

Cohesion is the property of water where the water molecules stick together due to the properties of hydrogen bonding. Plants use this property in order to transport water. As drop of water evaporates, it drags the rest of the water drops along behind it. A straw works much in the same way.

Water also moderates temperature, it takes a lot of energy to raise the temperature of water one degree. Water also releases heat slowly and this has the effect of regulating the Earth's temperature keeping it within the range to make it habitatable. It also the reason why tempetures are always so moderate near the ocean.

Water is an important molecule biologically because ice floats on water. This is because ice is less dense than water. The hydrogen bonds which break and reform in water become more permanent in ice. Therefore, water molecules in liquid water are closer together making it more dense. The is important because the ice isulates bodies of water like lakes or the ocean so that the whole body of water does not freeze. Only the top layer becomes frozen this allows the organisms living in the water body to survive the winter which they could not do if the body of water completely froze through.

The last important property of water is its use as a solvent. It is called the universal solvent because many different compounds will dissolve in it and many different types of chemical reactions can take place in it. All of the chemical reactions in your body take place in water.

Water is a very important biological molecule, if its chemical properties were any different then we could not live as we do today.

More about this author: Heather Lyon

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