Have you heard about the crisis in Antarctica?  Well just in case you have not heard, the ozone layer is slowly depleting in this part of the world and is  creating a huge hole.  The ozone layer, which is made of O₃,  is a region of the atmosphere above the earth's surface.  The ozone hole, which is more or less a thinning of the ozone layer, develops in the Antarctic spring and continues for several months before thickening again.
 

So why should we know about the deterioration of the ozone layer?

Well the main reason why this crisis should be important to all of us is due to the fact that ozone layer of the atmosphere protects life on earth from the sun's cancer causing ultraviolet radiation, which is very very important!  As a result of this crisis, chemists have had to investigate the many chemical reactions that are taking place in this particular part of our atmosphere.
 
 

What is a chemical reaction?

A chemical reaction is known as the process that occurs when one of more substances are combined together and they end up forming one of more different substances.  So why do chemical reactions occur?  Well, atoms are always zipping around.  If these atoms are bumping into each other and hitting each other with enough energy, they can break and form new bonds.  Therefore, a chemical reaction shows what changes take place when one or more substances react to form one or more different substances.  The starting substances in a chemical reaction are known as the reactants and the substances formed in the chemical reactions are the products.  If gases are real gases, they will most likely have enough energy to break and form bonds.  As a result, many chemical reactions can occur that involve gases as products and or reactants.

For example, the main reason why the ozone layer is forming a hole is due to the fact that chlorine-containing chemicals rise into the atmosphere and react with the ozone, O₃ and and actually destroys them.

More or less what happens is described by the following chemical equation:

Reactants --->    Products
 

Cl + O₃     ---->   ClO   + O₂

As a result, chemicals such as chlorofluorocarbons such as those used as refrigerants and as aerosol spray propellants should not be used because they pose a threat to our world.

Although scientists were able to determine why the ozone layer was forming a hole, our job as active citizens in our society is to help from contributing to making the hole get bigger.  Now that you know how the products you may use affect our world, it would be beneficial for you to tell others why it is important that we refrain from using products that contain chlorine-containing chemicals such as aerosol cans.

Another reason why we should study gases is due to the fact that they have a high potential of reacting because they are always present!

A lesson that involves a chemical reaction that forms a gas is in the Demo #4:  The Molecular Race.

Let's take a look at another chemical reaction that involves a gas.

Carbon monoxide is a colorless, odorless, and deadly gas.  In fact, it causes the deaths of hundreds of Americans each year.  When fuel undergoes a chemical reaction in which not all of the fuel does not burn completely, carbon monoxide is produced.  This often occurs when a heater, furnace, or even a fireplace is not working right.  When this gas is inhaled, it bonds with a molecule called hemoglobin, which is in blood and causes the body to be left with a lack of oxygen.

The actual chemical reaction that takes place is below:

Hemoglobin   Carbon monoxide
O₂Hb          +           CO     --->     COHb     + O₂

One of the many ways that carbon monoxide can be prevented is by installing filters that absorbs this gas and disposing of them when they become filled with carbon monoxide.

Since the chemical reaction of carbon monoxide attaching to hemoglobin in the body can cause death, it is important that we study gases.  One of the main reasons why we should study gases is due to the fact that we are surrounded by gases.  As a result, it is important how gases in our environment work so that we can protect ourselves from harm and understand why they react they way that they do.