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    Ammonia and Oxygen

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    The reaction of ammonia with oxygen (from the air) to form nitrogen monoxide (NO, also known as nitric oxide ) is the first stage in the industrial conversion of ammonia into nitric acid. At the temperatures used, the thermo chemical equation for the reaction is as follows:

    4NH3(g) + 502 <--->4NO(g) + 6H2 O(g) (delta)h=-906Kj

    a) Explain the following:

    i)The effect that increasing the temperature will have on the rate of the reaction.

    ii) The effect that increasing the temperature will have on the rate of the reaction

    Your answer to (a)(i) should include a clear statement of Le Chatelier's principle and should show clear understanding of how this principle applies to the situation described.

    b) In practice the process for producing NO from ammonia is operated at about 650oC in the presence of a platinum catalyst.

    Bearing in mind you answers to part (a), explain the role of the platinum catalyst, noting how its presence helps to maximize the equilibrium yield of NO whilst also ensuring a reasonable rate of production.

    © BrainMass Inc. brainmass.com December 24, 2021, 7:11 pm ad1c9bdddf
    https://brainmass.com/chemistry/le-chatelier-s-principle/ammonia-oxygen-169297

    SOLUTION This solution is FREE courtesy of BrainMass!

    (a) The reaction is exothermic. We know because the sign of (delta) H is negative. That means that heat is released in the reaction. Therefore, the heat appears on the right side of the reaction, among the products. LeChatalier's principle states that whenever we perturb a system it will react to restore equilibrium. Therefore, if we increase the temperature of the system, we are adding more heat. We are adding more heat to the right side of the equation. Therefore, the reaction will shift to the left. In order to move toward equilibrium, the reaction will be shifted more to the reactants, not the products.

    (b) Now, if we do the reaction at high temperature, it wouldn't seem like a smart thing to do. However, if we add a catalyst, then we can overcome the effect of LeChatalier's principle. How is this? Because a catalyst lowers the activation energy for a reaction. It lowers the "energy hump" required to get reactants to form products. Another way to say it is that it lowers the energy needed to get to the transition state. As a result, the kinetics of the reaction increase. The rate of reaction increases and more reactants will convert into product even at this higher temperature.

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    © BrainMass Inc. brainmass.com December 24, 2021, 7:11 pm ad1c9bdddf>
    https://brainmass.com/chemistry/le-chatelier-s-principle/ammonia-oxygen-169297

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