k & K

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Diana Sandoval 1K
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k & K

Postby Diana Sandoval 1K » Fri Mar 08, 2019 8:30 am

What is the difference between k in kinetics and K in equilibrium/ thermo?

Ray Huang 1G
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Re: k & K

Postby Ray Huang 1G » Fri Mar 08, 2019 8:51 am

k in electro should be Boltzmann's constant while k in kinetics is a number unique to each reaction scaling how quickly the reaction proceeds.

Anushi Patel 1J
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Re: k & K

Postby Anushi Patel 1J » Fri Mar 08, 2019 10:00 am

To add to the previous answer, K in thermodynamics is the equilibrium constant, which describes the concentrations of reactants and products at equilibrium, and doesn’t have anything to do with the speed of the reaction.

Nico Edgar 4L
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Re: k & K

Postby Nico Edgar 4L » Fri Mar 08, 2019 11:14 am

k is a rate constant dependent on the reaction you have. K is the equilibrium constant.

Jennifer Lathrop 1F
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Re: k & K

Postby Jennifer Lathrop 1F » Fri Mar 08, 2019 12:34 pm

how do you know when to use it as a Boltzmann's constant or a rate constant?

Jennifer Lathrop 1F
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Re: k & K

Postby Jennifer Lathrop 1F » Fri Mar 08, 2019 12:34 pm

or are those the same?

Gracie Ge 2E
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Re: k & K

Postby Gracie Ge 2E » Sat Mar 09, 2019 5:26 pm

isn't boltzmann's constant used to calculate entropy with the number of possible states of a molecule and the number of molecules?
rate constants and boltzmann are entirely different things.

Amy Dinh 1A
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Re: k & K

Postby Amy Dinh 1A » Sat Mar 09, 2019 11:27 pm

k is Boltzmann constant, which is equal to 1.38064852 × 10^-23 m2 kg s^-2 K^-1. K is the equilibrium constant of a reaction, which is calculated by the concentration of the products over concentration of the reactants.

Lumbini Chandrasekera 1B
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Re: k & K

Postby Lumbini Chandrasekera 1B » Sat Mar 09, 2019 11:38 pm

k is the Boltzmann rate constant while K is the equilibrium constant for a certain reaction.

maldonadojs
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Re: k & K

Postby maldonadojs » Sat Mar 09, 2019 11:48 pm

I am sure the question will tell us to use the k as a rate constant in kinetics in the question, whereas the k Boltzmann constant will be used to calculate the entropy. K will be given in an acids and base question. It is based off of context.

Krista Mercado 1B
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Re: k & K

Postby Krista Mercado 1B » Sun Mar 10, 2019 12:44 pm

The difference is that k is Boltzmann's constant, while K is the equilibrium constant for a given reaction.

Aarti K Jain 1L
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Re: k & K

Postby Aarti K Jain 1L » Sun Mar 10, 2019 1:16 pm

In kinetics, k is the rate constant, whereas K is the equilibrium constant. Also, K = k/k', which means the the equilibrium constant is equal to the ratio of rate constants of the forward (k) and the reverse (k') elementary reactions.

allisoncarr1i
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Re: k & K

Postby allisoncarr1i » Wed Mar 13, 2019 10:16 am

lower case k is the boltzmann constant and upper case K is the equilibrium constant

Kyither Min 2K
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Re: k & K

Postby Kyither Min 2K » Wed Mar 13, 2019 2:35 pm

k is the rate constant so it's basically an indicator of how fast the reaction will happen. K is the equilibrium constant that tells you the ratio of products to reactant concentrations when the reaction is at equilibrium. Based on the relationship between k and K, we can determine that the forward reaction's rate constant, k will be larger than the reverse reaction rate constant if K (equilibrium constant) is larger than 1.

Megan_Ervin_1F
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Re: k & K

Postby Megan_Ervin_1F » Wed Mar 13, 2019 8:42 pm

It is also important to note that K can be figured out by taking the ratio of the forward reaction K to the reverse reaction K

Melissa Villanueva1K
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Re: k & K

Postby Melissa Villanueva1K » Fri Mar 15, 2019 10:33 pm

Will there be a clear indication of 'k' and 'K' on the final? Such as bolding one over the other. Thanks.

Ashley P 4I
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Re: k & K

Postby Ashley P 4I » Sat Mar 16, 2019 12:32 pm

Melissa Villanueva1K wrote:Will there be a clear indication of 'k' and 'K' on the final? Such as bolding one over the other. Thanks.

Do you mean on the constants and equations sheet?

Milena Aragon 2B
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Re: k & K

Postby Milena Aragon 2B » Sat Mar 16, 2019 2:02 pm

Melissa Villanueva1K wrote:Will there be a clear indication of 'k' and 'K' on the final? Such as bolding one over the other. Thanks.


I think in order to avoid confusion, it may be written out for us along with the variable e.g. "the rate constant, k,..."

JacobHershenhouse3G
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Re: k & K

Postby JacobHershenhouse3G » Sat Mar 16, 2019 2:23 pm

K is the equilibrium constant and kr is the rate constant, symbolizing different constant values with different meanings, applied in different equations but they are related. K is equal to the overall forward rate constant over the reverse rate constant because at equilibrium the forward and reverse rates (not the constants) are equal.


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