Units for K

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Alexis Robles 2k
Posts: 100
Joined: Wed Sep 18, 2019 12:18 am

Units for K

Postby Alexis Robles 2k » Sun Jan 12, 2020 5:35 pm

So we do not use units for K? Can someone explain this to me?

Tiffany Chao 2H
Posts: 117
Joined: Fri Aug 09, 2019 12:17 am

Re: Units for K

Postby Tiffany Chao 2H » Sun Jan 12, 2020 5:40 pm

No because K is a constant. We use brackets around equilibrium concentration. The brackets indicate molar concentration so we omit actual units.

Jasleen Kahlon
Posts: 52
Joined: Wed Nov 21, 2018 12:19 am

Re: Units for K

Postby Jasleen Kahlon » Sun Jan 12, 2020 5:42 pm

K is representative of a ratio, products/reactants. It is used to compare rates of reaction and therefore does not have units.

chrisleung-2J
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Re: Units for K

Postby chrisleung-2J » Sun Jan 12, 2020 5:49 pm

Neither K nor Q have units

William Chan 1D
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Joined: Sat Sep 14, 2019 12:15 am

Re: Units for K

Postby William Chan 1D » Sun Jan 12, 2020 5:51 pm

K doesn't have units technically because they all cancel out, and it comes out to be just a number ratio.

205154661_Dis2J
Posts: 109
Joined: Wed Sep 18, 2019 12:21 am

Re: Units for K

Postby 205154661_Dis2J » Sun Jan 12, 2020 5:52 pm

Equilibrium constants have no units; this is because it is a ratio of similar quantities.

TanveerDhaliwal3G
Posts: 105
Joined: Fri Aug 30, 2019 12:17 am

Re: Units for K

Postby TanveerDhaliwal3G » Sun Jan 12, 2020 5:56 pm

K doesn't have units because it is a ratio of molar concentrations.

CalvinTNguyen2D
Posts: 102
Joined: Thu Jul 25, 2019 12:16 am

Re: Units for K

Postby CalvinTNguyen2D » Sun Jan 12, 2020 8:22 pm

K does not have any units associated with it, since it's just a ratio of different molecules and species.

SVajragiri_1C
Posts: 115
Joined: Thu Jul 11, 2019 12:16 am

Re: Units for K

Postby SVajragiri_1C » Sun Jan 12, 2020 8:37 pm

K is a constant because when calculating it all the units cancel out, so there is no unit for it.

kendal mccarthy
Posts: 109
Joined: Wed Nov 14, 2018 12:22 am

Re: Units for K

Postby kendal mccarthy » Sun Jan 12, 2020 10:03 pm

K is a constant, meaning there are no units used. But, it is a good way to check your work if you end up with units because there should not be any because they should all cancel out.

Eesha Chattopadhyay 2K
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Joined: Fri Aug 09, 2019 12:16 am

Re: Units for K

Postby Eesha Chattopadhyay 2K » Sun Jan 12, 2020 10:16 pm

In class, Dr. Lavelle mentioned briefly saying that technically K is the ratio if the activities of the products and reactants, which is unit-less.

Morgan Carrington 2H
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Joined: Wed Nov 14, 2018 12:22 am

Re: Units for K

Postby Morgan Carrington 2H » Sun Jan 12, 2020 10:28 pm

Since K is a ratio of values with the same units, they cancel out and are not present in the K value. I would still include them in the K expression to show my work though!

SVajragiri_1C
Posts: 115
Joined: Thu Jul 11, 2019 12:16 am

Re: Units for K

Postby SVajragiri_1C » Sun Jan 12, 2020 10:41 pm

There is no unit for K, it is a constant for equilibrium. You can prove this because when you solve for K, all the units cancel out.

Veronica Lu 2H
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Re: Units for K

Postby Veronica Lu 2H » Sun Jan 12, 2020 11:40 pm

There are no units since K is more so a ratio

Angela Wu-2H
Posts: 50
Joined: Fri Aug 30, 2019 12:16 am

Re: Units for K

Postby Angela Wu-2H » Sun Jan 12, 2020 11:58 pm

K has no units because of "activity"; however, activity is really low (close to 1) for the most part, so the equation ratio is simplified to the form that we know. But also, in the ratio, the units in the numerator and denominator will cancel out.

Mitchell Koss 4G
Posts: 128
Joined: Sat Jul 20, 2019 12:17 am

Re: Units for K

Postby Mitchell Koss 4G » Mon Jan 13, 2020 11:34 am

K has no units but units you plug in matter, so use mol/L not mL or mol.

105335337
Posts: 103
Joined: Sat Aug 24, 2019 12:15 am

Re: Units for K

Postby 105335337 » Mon Jan 13, 2020 12:28 pm

K has no units as hen you do all the calculations, the units cancel out. Furthermore, this is because K is just a constant.

pmokh14B
Posts: 107
Joined: Sat Aug 17, 2019 12:15 am

Re: Units for K

Postby pmokh14B » Mon Jan 13, 2020 12:29 pm

K does not have units it is a constant.

Kallista McCarty 1C
Posts: 212
Joined: Wed Sep 18, 2019 12:18 am

Re: Units for K

Postby Kallista McCarty 1C » Mon Jan 13, 2020 1:41 pm

Since K is a constant it does not have units associated with it!

Jainam Shah 4I
Posts: 130
Joined: Fri Aug 30, 2019 12:16 am

Re: Units for K

Postby Jainam Shah 4I » Mon Jan 13, 2020 10:23 pm

K does not have units. The brackets signify its molarity or concentration of a reactant or product. As Dr. Lavelle discussed in class the true way to explain is via the ratio of the activities of the reactants and product. K is simply giving us the relative information of the rates and which reaction is favored. Activities don't have units and the expression we write assumes the activities are close to 1.

805422680
Posts: 103
Joined: Sat Sep 14, 2019 12:16 am

Re: Units for K

Postby 805422680 » Mon Jan 13, 2020 11:29 pm

K does not have units as it is a constant value of the ratio of concentrations of products to reactants.

Celine 1F
Posts: 120
Joined: Fri Aug 02, 2019 12:16 am

Re: Units for K

Postby Celine 1F » Tue Jan 14, 2020 9:33 am

K, a constant, demonstrates the ratio of products and reactants so it does not have units


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