Catalysts and Intermediates
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Catalysts and Intermediates
What are the defining characteristics of a catalyst versus an intermediate?
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Re: Catalysts and Intermediates
Catalysts are not consumed during the course of a reaction. They are used to lower the activation energy so that more molecules, at the same temperature, have the minimum required energy to reach the transition state. Catalysts speed up the rate of the forward and reverse reaction, so they do not affect the equilibrium composition. You can identify catalysts in reaction mechanisms by checking for which substance first appeared as a reactant and later as a product.
Intermediates are substances that are temporarily formed by reactants, but are later consumed to form products. You can identify intermediates in reaction mechanisms by checking for which substance is first present on the products side and later seen as a reactant.
Intermediates are substances that are temporarily formed by reactants, but are later consumed to form products. You can identify intermediates in reaction mechanisms by checking for which substance is first present on the products side and later seen as a reactant.
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Re: Catalysts and Intermediates
Intermediates are typically consumed within their reaction, whereas catalysts are not consumed.
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Re: Catalysts and Intermediates
You can tell if a something is a catalyst or intermediate in a mechanism depending on where it is located on the elementary steps. If something is a catalyst, it'll be a reactant in the initial elementary step and a product in the 2nd elementary step. An intermediate will be a product in the first elementary step and a reactant in the 2nd elementary step.
Re: Catalysts and Intermediates
Catalysts lower the activation energy in order to speed up the rate of the forward & reverse reaction.
Intermediates are formed by reactants but later consumed in the production of final products, while catalysts aren't consumed. Hope this helps!
Intermediates are formed by reactants but later consumed in the production of final products, while catalysts aren't consumed. Hope this helps!
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Re: Catalysts and Intermediates
Catalysts are not consumed during the course of a reaction. They are always canceled out in a series of elementary steps, so they are typically on the reactant side in one step and product side in another. They reduce the activation energies of both the forward and reverse reactions, thus increasing the rates. Catalysts never appear in the rate equation.
Intermediates are substances that are formed by reactants in one step, but are later consumed to form products in the following. They never appear in the rate equation.
Intermediates are substances that are formed by reactants in one step, but are later consumed to form products in the following. They never appear in the rate equation.
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Re: Catalysts and Intermediates
Achieve #18 provides an example of this. The catalyst is consumed in one reaction, and then produced in the other, and an intermediate is produced and the consumed.
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Re: Catalysts and Intermediates
Catalysts do not contribute to the products while intermediates do. You can tell the difference by comparing the chemical makeup of the catalyst or intermediate to the products and reactants.
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