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How does the presence of a catalyst affect the reaction rate of a chemical reaction between hydrogen peroxide and potassium iodide? And how does the rate of the reaction change when different amounts of catalyst are used?

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The presence of a catalyst in a chemical reaction between hydrogen peroxide  H2O2  and potassium iodide  KI  significantly increases the reaction rate. A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. In this case, the catalyst lowers the activation energy required for the reaction to occur, allowing it to proceed at a faster rate.The reaction between hydrogen peroxide and potassium iodide can be represented by the following equation:2 H2O2  aq  + 2 KI  aq   2 H2O  l  + O2  g  + 2 KI  aq In this reaction, a common catalyst used is potassium iodide  KI  itself or a soluble iodide salt. The iodide ions  I-  from the catalyst react with hydrogen peroxide to form iodine  I2  and water  H2O . The iodine then reacts with more hydrogen peroxide to regenerate the iodide ions, which can continue to catalyze the reaction. This cycle is known as the iodine clock reaction.When different amounts of catalyst are used in the reaction, the rate of the reaction will change accordingly. If more catalyst is added, the reaction rate will increase because there are more catalyst molecules available to lower the activation energy and facilitate the reaction. Conversely, if less catalyst is used, the reaction rate will decrease due to fewer catalyst molecules being available to interact with the reactants.It is important to note that there is a limit to how much the reaction rate can be increased by adding more catalyst. At a certain point, the reaction rate will reach a maximum, and adding more catalyst will not have any further effect. This is because the reaction rate becomes limited by other factors, such as the concentration of the reactants or the available surface area for the reaction to occur.
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