ShmoopTube

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Here’s your Shmoop du jour, brought to you by rockets.

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They rock so much, they put it in the name. [Engineers working on a rocket]

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Okay, here’s our question:

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Nitrogen dioxide is a substance that is sometimes used in rocket fuel.

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Nitrogen dioxide is prepared according to the following reaction, riiiiight…here….

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And the rate law for this reaction is Rate = k[NO]2[O2].

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< The rate constant times the concentration of NO times the concentration of o2> [Rate law and reaction example]

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What would happen to the rate of the reaction if the concentration of NO were doubled, and

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the concentration of O2 remained the same?

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And here are the potential answers: [mumbling]

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Before we launch right into this problem, let’s lift off our spirits with this fuel for [Boy tied to a rocket and the rocket sets off]

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thought.

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Many NASA astronauts have been chemists, so if you stick with this chemistry stuff, and

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take some time to planet all out, you too could become an astronaut…[woman astronaut holding chemical substance and it explodes]

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And that would be out of this world.

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Now that we’ve run out of space for these astronomically terrible puns, let’s get [woman lab worker holding two erlenmeyer flasks]

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back to the problem.

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We’re given the rate law for the rocket fuel synthesis reaction.

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The rate equals the concentration of NO squared times the concentration of O2.

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The concentration of O2 is kept constant.

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If we double the concentration of NO into this equation, the rate will increase by a

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factor of four, since the concentration of NO is squared in the rate law.

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And what that means is we don't have to drag anything out and we can just go ahead and [Students yawning in a classroom]

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tell you that the correct answer is (D), “The rate would quadruple.”

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Phew.

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Isn't it nice when things are simple?

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Like going into space.

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It's easy-peasy, right?

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But uh…just to be on the safe side, maybe you should trade in that rocket and get your [Man lands in a store on a rocket and demands a refund for his car]

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car back.

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