Catalysts in Living Organisms
Enzymes are biological catalysts that work to speed up reactions that occur in living
organisms.
Catalysts help to place reactants in the proper orientation so that they can have an
effective collision. An effective collision is one that leads to the formation of the
product.
An example is the synthesis of peptides. Peptides are long molecules made up of amino
acids that are linked together by the action of enzymes. These peptide molecules then
go on to form proteins.
Catalysts in the Haber Process
Ammonia (NH3) is widely used today and must be produced at an industrial level. It is
used mainly in fertilizers, cleaning products and in the production of pharmaceuticals. It
is estimated that 200 million tonnes of industrial ammonia is produced every year
worldwide.
The production of ammonia consists of combining hydrogen gas to nitrogen gas from air.
N2 (g) + H2 (g) -> 2 NH3 (g)
In order to have a greater yield (production) of ammonia, one must increase the rate of
reaction. Increasing the pressure is not possible because modern equipment is not
resistant to such forces. Increasing the temperature is possible through the use of
fossil fuels, however it is highly costly. To solve this dilemma, Fritz Haber, a German
Chemist, developed a process in 1910 that takes advantage of the properties of
catalysts. The catalysts lower the activation energy of the reactants thereby reducing
the amount of heat needed to trigger the reaction. The temperature of the reaction
vessels can be lowered without losing any yield. This economically efficient process is
now the preferred method of producing ammonia.
Homework Questions 4.18- 4.20