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Thank you We sneak and here's your shmoop du jour

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Brought to you by units No not your great aunt

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eunice units man your hearing's getting as bad as your

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aunt units if rate is measured in mole's per liter

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per second concentration is measured in miles per leader What

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is the correct units for a second order rate Constant

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and your potential answers All right You know i get

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asked that a lot of cocktail parties Okay well this

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problems asking about the units for a rape constant but

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there's a catch It doesn't give us the equation for

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the rate law told so let's start by writing the

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reaction rate law equation right there Rika rate law tells

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us the reaction rate as a function of the rate

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constant in the concentration of the reactant way don't know

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what the reactant are but we do know that the

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reaction is second order it's hoping to make the order

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of the phoenix by the end of the year But

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you don't have to put in it's time for us

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Okay so the reaction order refers to the exponents on

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the concentrations of the reacting species in the rate law

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If we have only one reactant a then the concentration

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of a must be squared in this equation Well the

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question asked us to find the units on the rape

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constant k Unfortunately we're given the units for the other

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terms in the equation Good thing we wore our lucky

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underwear today All right so here's the trick Since the

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concentration of a is squared the units on a mole's

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per leader are also squared After that all we have

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to do to find the units on k is a

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little math We have to isolate the unknown then group

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the same units together and cancel out terms by term

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correct units for the rate constant our leaders per mall

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for second which is answer c Now how would you

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rate that constant We'd give it five girl and meyer 00:01:48.966 --> [endTime] flasks

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