Some chemical reactions are very fast and others are very slow. We want to speed up some reactions, for example the conversion of polluting gases in car exhausts to less harmful chemicals. To do this cars are fitted with a catalytic converter. These contain catalysts. Catalysts are substances that speed up chemical reactions without getting used up themselves. The catalyst is still there when the reaction has finished. This makes catalysts very useful as they can be used again and again. They are used in lots of industrial processes so that the product can be made faster. Commonly, transition metal salts are used as catalysts. They provide new routes for chemical reactions with lower energy barriers than the original reaction routes. In this experiment you will be using a cobalt (II) salt as a catalyst for a chemical reaction and observing the changes as it speeds up the reaction.