Calculating K

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Brandon Tao 1K
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Joined: Sat Aug 17, 2019 12:15 am

Calculating K

Postby Brandon Tao 1K » Sun Jan 12, 2020 6:12 pm

Why is water not accounted for in calculating for K?

sbeall_1C
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Re: Calculating K

Postby sbeall_1C » Sun Jan 12, 2020 6:13 pm

K does not include pure liquids or solids, merely aqueous solutions and gases!

TarynD_1I
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Joined: Sat Aug 24, 2019 12:17 am

Re: Calculating K

Postby TarynD_1I » Sun Jan 12, 2020 6:14 pm

Water is not accounted for when calculating for K because it does not affect the equilibrium of the reaction. Pure solids and pure liquids usually do not affect K and are not included in its calculation expression.

Jeremy_Guiman2E
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Joined: Fri Sep 28, 2018 12:29 am

Re: Calculating K

Postby Jeremy_Guiman2E » Sun Jan 12, 2020 10:02 pm

Pure liquids and solids don't affect the reactant amount as their concentrations stay the same.

ShastaB4C
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Joined: Thu Sep 26, 2019 12:18 am

Re: Calculating K

Postby ShastaB4C » Sun Jan 12, 2020 10:06 pm

Would there be any solvent in which we would include it in K calculations?

sarahartzell1A
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Joined: Fri Sep 28, 2018 12:17 am

Re: Calculating K

Postby sarahartzell1A » Sun Jan 12, 2020 11:04 pm

Water is not accounted for because it is a pure liquid!

Rafsan Rana 1A
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Joined: Sat Aug 24, 2019 12:16 am

Re: Calculating K

Postby Rafsan Rana 1A » Sun Jan 12, 2020 11:12 pm

pure liquids and solids, which includes water, are disregarded for the equilibrium expression because they don't have an affect on reactant amount at equilibrium and they don't have a concentrations to be used to calculate k.

Bryan Chen 1H
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Joined: Mon Jun 17, 2019 7:24 am

Re: Calculating K

Postby Bryan Chen 1H » Sun Jan 12, 2020 11:41 pm

water is a pure liquid and a solvent. while it "takes part" in the reaction, the change is so small its negligible

Vivianvelazquez_1J
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Re: Calculating K

Postby Vivianvelazquez_1J » Sun Jan 12, 2020 11:51 pm

When calculating K water is not accounted for because the molar concentration of pure substances (solids or liquids) does not change in the reaction. Therefore solid and liquids are not included in the K expression.

Sofia Barker 2C
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Joined: Wed Sep 18, 2019 12:21 am

Re: Calculating K

Postby Sofia Barker 2C » Mon Jan 13, 2020 12:00 am

Water is not accounted for because it is considered a pure liquid. Pure liquids don't undergo a change in concentration during a reaction, so it is not necessary to calculate their equilibrium concentrations.


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