K value- Temp

$\ln K = -\frac{\Delta H^{\circ}}{RT} + \frac{\Delta S^{\circ}}{R}$

Julia Go 2L
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K value- Temp

Why does the value of K change when the temperature changes?

Kathryn Wilhem 1I
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Re: K value- Temp

Using leChatelier's principle, when the temperature is changed, depending on whether the reaction is endothermic or exothermic, the reaction will favor either the reactants or the products. We use the equation -deltaH/R(1/T2 - 1/T1) = ln(K2/K1) to find what the new K is when the temperature is changed.

almaochoa2D
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Re: K value- Temp

If you remember temperature is the only thing that can change K.

anthony_trieu2L
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Re: K value- Temp

In addition, in order to use the equation stated above, you must assume that delta H and delta S are constant. This equation allows us to determine K at different temperatures is these values (delta H and delta S) are known.

Nicolle Fernandez 1E
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Re: K value- Temp

When temperature changes a reaction will either favor reactants or products more which means K will change.

LedaKnowles2E
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Re: K value- Temp

A temperature change pushes the reaction to either the left or right depending on whether heat is a reactant or product (depending on whether the rxn is exo or endothermic). This gives the reaction a new equilibrium point, so k changes.

Jack Hewitt 2H
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Joined: Fri Sep 28, 2018 12:27 am

Re: K value- Temp

Temperature is the only thing that can change the value of K.