What is Catalysis?
Catalysis is the speeding up of a chemical reaction by adding a catalyst (a substance that can be added to a chemical reaction to speed it up, and it is not consumed during the reaction). Catalyst reduces the activation energy (the least amount of energy that is needed to initiate a chemical reaction), which increases the reaction rate (the speed at which the reactant is converted into the product).
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Types of Catalysts
There are two major types of catalysts: heterogeneous catalysts and homogeneous catalysts.
1. Heterogeneous Catalyst
Heterogeneous catalyst is a catalyst which is in a different phase (solid, liquid, or gas) with the reactant(s). Ethylene (C2H4) and hydrogen gas (H2) reacting to form ethane (C2H6) with the help from catalysts such as nickel, palladium, and platinum is one of the examples of homogeneous catalysis. In this case, reactants, ethylene and hydrogen gas, are in gas phases while the catalysts are in solid phases.
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2. Homogeneous Catalyst
Homogeneous catalyst is a catalyst which is in the same phase with the reactant(s). A good example of homogeneous catalysis would be when dichlorodifluoromethane (CCl2F2, commonly known as freon gas) reacts with ozone (O3) and UV light with the help from chlorine radical catalyst to form oxygen gas. In this case, both reactants and catalyst are in gaseous form.
Catalysts in Real Life
Catalysts can be found in our daily lives. One example is enzymes. Enzymes can be easily determined with their names ending with -ase. Enzymes in our digestive system such as diastase and lactase helps our bodies digest food. Also, DNA polymerase, another type of enzyme, catalyzes the synthesis of DNA. Catalysts can be also found in engines in vehicles. Platinum catalysts lining up in the motor of the vehicle can convert carbon monoxide, which is toxic, into carbon dioxide.
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