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Question:

Explanation of Catalysts?

What is a catalyst in a chemical reaction?

Answer:

A catalyst is a compound in chemistry (it can be an acid or temperature or a base or a metal or anything, pressure anything) that shifts the reaction towards one product or the other... In simple words. If you want to obtain something, e.g. water, then you can obtain it in different timings, ie in 2000 years, but if you want to obtain it in 2 hours instead of 2000 years then you add a catalyst, e.g. you heat the reaction to speed it up, you add an acid, or a base etc. Some catalysts also act on the regioselectivity of a compound thru preferring the formation of a stereo-isomer to another. E.g. if you want to obtain S-Thalidomide instead of R-Thalidomide you use a particular catalyst etc...
I didn't actually need to know what a catalyst was for my chemistry exam just what it does. A catalyst is something that speeds up a chemical reaction.
A catalyst increases the rate of a reaction by lowering the activation energy. Activation energy is the energy required to make the reactants form the products. If the activation energy is lower the reaction takes place faster and more easily. Also catalysts are not used up during the reaction.
Hi Ganah! A catalyst is a substance that increases the rate of a chemical reaction without itself being used up in the reaction. They lower the activation energy for a reaction and also speed up the rate of the reaction (both in reverse and forward reactions). Let's look at a generic chemical reaction: A + B---C + D C + D---B + E Here, the catalyst is substance B because it is part of the chemical reaction but then it is not used up in the net reaction. See how it seems to be used up in the first step, but by the second step, the catalyst is made once again. The net reaction is A + B--->B + E and you can see how it is not consumed in the reaction. There are also 3 types of catalysts. Heterogeneous catalysts are catalysts that are in different phases than the reactants. An example would be like a reaction between two solids but a liquid is added to speed up the reaction. The liquid is in a different state of matter than the solids but it can still function as a heterogeneous catalyst. Homogeneous catalysts are catalysts that are in the same states of matter as the reactants. An example would then be ethyl acetate reacting with water to form acetic acid and ethanol with an acidic catalyst. They would all be liquids. Lastly, there are enzyme catalysts. These are proteins in your body that speed up biological reactions by reacting with substrates. I hope this helped and good luck with chem!
A catalyst provides an alternative reaction pathway with a lower activation energy. So it speeds up the rate of reaciton because the energy of the particles/reactants doesnt have to be that high to OVERCOME the activation energy so it can therefore react. The activation energy is the minimum amount of energy required for particles to react, so the lower it is, the more faster a rate of reaction will be.

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