Catalysts in Reactions

Catalysts are substances that speed up chemical reactions without being used or chemically changed in the process. This means that the mass of the catalyst remains the same before and after the reaction.

Catalysts are specific in the sense that they only work with certain types of chemical reactions. A catalyst will only work if it can interact with the reactants in a way that speeds up the reaction. This is why different catalysts are used for different chemical reactions.

You only need a small amount of a catalyst to speed up a chemical reaction. Using more of the catalyst than necessary won’t significantly increase the reaction rate. Using more of the catalyst than needed will not make the reaction happen much faster

Enzymes are biological catalysts that speed up chemical reactions in living organisms. For example, amylase catalyses the breakdown of starches (complex carbohydrates) into simpler sugars such as glucose.

Catalytic Converters

The exhaust systems of cars contain catalytic converters, which reduce the release of toxic pollutants from the exhaust pipe. They do this by converting harmful substances into less harmful substances.

Three pollutants that catalytic converters target are nitrogen oxide, carbon monoxide and hydrocarbons.

  • Nitrogen oxides can lead to the formation of smog and acid rain. The catalytic converter changes these pollutants into nitrogen and oxygen, which are less harmful to the environment.
  • Carbon monoxide is a colourless and odourless gas that is toxic to humans and animals when inhaled. The catalytic converter converts carbon monoxide into carbon dioxide, which is less harmful.
  • Hydrocarbons are found in gasoline and inhaling them can be fatal, especially to children. The catalytic converter converts hydrocarbons into carbon dioxide and water.

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