ShmoopTube

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And here’s your Shmoop du jour, brought to you by decreasing the temperature.

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Turn down for what? …because it’s too hot in here. [Man crushes a table and dances]

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Here’s today’s question:

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Which of the following is true regarding rates of chemical reactions?

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And here are your potential answers:

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This question is about reaction rates, by which we don’t mean how long it takes you [Man on stage telling jokes]

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to start laughing after we tell a hilarious joke.

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We’re talking about chemistry here, guys.

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Get with it.

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There are a few tried and true ways to speed up chemical reaction rates. [Scientist transferring substance to a beaker and it explodes]

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Let’s imagine that each time two of these red molecules react, they create one blue [Red molecules collide and create blue molecule]

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molecule.

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To increase the reaction rate, we could increase the concentration of the reactants.

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This would lead to more collisions between the reacting molecules, which would cause [Molecules colliding]

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the reaction rate to increase.

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That’s pretty straightforward, right?

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Another way we could increase the reaction rate would be to use a catalyst.

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Because that’s the whole point of catalysts.

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Seriously.

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That’s all they do.

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They’re kind of a one-trick pony.

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Catalysts work by decreasing activation energy barriers so molecules that collide are more [Catalysts in a beaker with molecules]

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likely to react.

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And if you’ve ever witnessed two angry people bumping into each other, you’ll know that [Two guys bump into each other]

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people that collide are also pretty likely to react.

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And last, but not least, we could also speed up a reaction by turning up the heat. [Fire burning]

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Besides keeping us nice and toasty, increasing the temperature can speed up a chemical reaction

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by giving reacting molecules more kinetic energy.

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This makes them collide more frequently and with more energy, so they’re more likely [Molecules colliding frequently]

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to overcome the activation barrier and react.

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Which is why if you go to a hot yoga class, you’ll see a lot of people falling over [Boy in yoga class falls over]

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each other.

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That’s how that works, right?

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Hey, that last method sounds really similar to answer B, which says that chemical reaction

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rates can be increased by increasing the temperature.

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And wouldn't you know it, the answer is B. Did you get it right? [Man with hair on fire running and screaming]

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We bet you did.

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You are on fire today. [Man uses fire extinguisher on mans head]

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