A chemical reaction is a reaction in which the compounds (i.e. the reactants) undergoing the reaction may experience any chemical change or an effect after going through the whole chemical process. But apart from the reactants, products and the by-products there are number of factors involved in a chemical reaction which makes the reaction’s inference reach the expected lines. One of the most important factors of the above mentioned one is the catalyst. A catalyst is basically a substance that alters the rate or speed at which a chemical reaction is proceeding. A catalyst mostly speeds up a chemical reaction where as some of the catalysts slow down that particular chemical reaction since some reactions may require more environmental time to get cooled down or broken down in some rare cases. The most important fact to be noted while studying about catalyst is that a catalyst only changes the rate of a certain reaction but does not get involved in the chemical reaction. Some of the most used catalysts are heat and water which naturally act as great influencers of a chemical reaction. The following discussion presents a brief summary of catalysts. A chemical reaction that involves a catalyst is called catalysis.
Types of Catalysts
There are primarily three broad types of catalysts which are presented below as follows.
Homogeneous catalysts
Homogeneous catalysts are catalysts that are in the same phase of matter (solid, liquid, gas) as the reactants of that particular reaction. This kind of catalysis is known as homogeneous catalysis. One of the most common examples of homogeneous catalysis is esterfication of carboxylic acids.
Heterogeneous catalysts
Heterogeneous catalysts are catalysts that are in different phase of matter when compared to the reactants of the particular chemical reaction. The catalyst may be any of the three states but not of the same state as that of the reactants. The most popular and best example of heterogeneous catalysts reaction is the Haber’s process where solid iron acts as a catalyst but the reactants nitrogen and hydrogen are gases. These two are the broader categories but the third type is as follows.
Enzymes
Enzymes are natural catalysts that are present in our body. Enzymes do not actively take part in all the functional processes of our system but they, just like other catalysts speed up the digestion and other functions. The performance of enzymes depends upon the diet and condition of the person. These are the types of catalysts. The properties are as follows.
Properties
As mentioned earlier, catalysts do take active part in a chemical reaction. However there are some unique properties of a catalyst which are as follows.
a. Catalysts do not get involved in a chemical reaction. They just alter the rate at which a reaction is progressing.
b. Only a small quantity of catalyst is generally used in a chemical reaction.
c. Catalyst cannot initiate a reaction whatsoever.
d. Catalyst is specific in its action.
e. Catalyst cannot alter the equilibrium of a chemical reaction.
These are the general characteristics of catalysts which are used to a great deal in almost most of all chemical reactions. There are many researches and studies going on the application of related and appropriate catalysts to all chemical reactions which makes it an even broader field to work on in the future.