Oxidation
General Overview
Oxidation is a type of chemical reaction that can be described in three different ways.
1. The addition of oxygen.
2. The loss of hydrogen.
3. The loss of electrons.
A common example of the first type of oxidation reaction would be the rusting of iron (Fe). In this example the iron is oxidized by oxygen resulting in iron oxide.

4 Fe + 3 O2 ----------> 2 Fe2O3
An example of the second type of oxidation reaction would be the oxidation of ethanol (CH3CH2OH). In this example, the hydrogen is lost from the ethanol and forms acetaldehyde (CH3CHO).

CH3CH2OH + O2 ----------> CH3CHO + H2O
An example of the final type of oxidation would be the oxidation of sodium (Na) by bromine (Br). In this example an electron that has a negative charge is taken from the sodium by the bromine.

2 Na + Br2 ----------> 2 Na+1 + 2 Br-1
Specific Application
Oxidation reactions occur when potassium permanganate (KMnO4) and chlorine gas (Cl2) are added to the raw water. The KMnO4 breaks down larger molecules that contribute to odor and taste of the water. Cl2 and KMnO4 both attack organic molecules that are found in the raw water that enters the plant.

To better illustrate this process, think of your dinner. Say for example that you are eating a large steak. If you try to consume the entire portion at once you will most likely suffocate and thus not succeed at eating the steak. However, if you simply cut the steak into smaller pieces you will be able to consume each one individually. This mimics the oxidation process. The Cl2 and KMnO4 both act as the knife to break down the organic molecules that would suffocate the treatment process.

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