Water in K constant

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Sanjana Borle 2K
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Joined: Fri Aug 09, 2019 12:15 am

Water in K constant

Postby Sanjana Borle 2K » Thu Jan 23, 2020 10:16 am

Is water included in the K constant expression if it is a gas? Is it only not included when it is a solvent?

Ally Huang- 1F
Posts: 103
Joined: Thu Jul 25, 2019 12:16 am

Re: Water in K constant

Postby Ally Huang- 1F » Thu Jan 23, 2020 10:49 am

Yes, water is included in the K constant if it is a gas because gasses can be written as a concentration and it is not the solvent. If it is a liquid it will not be in the K constant expression.

kristi le 2F
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

Re: Water in K constant

Postby kristi le 2F » Thu Jan 23, 2020 11:40 am

water is not included in the K constant when it is a solvent because it is viewed as pure. Liquids and solids are not included in the K constant since their concentrations do not significantly change.

Abby Soriano 1J
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Joined: Sat Aug 24, 2019 12:16 am

Re: Water in K constant

Postby Abby Soriano 1J » Thu Jan 23, 2020 11:58 am

kristi le 2F wrote:water is not included in the K constant when it is a solvent because it is viewed as pure. Liquids and solids are not included in the K constant since their concentrations do not significantly change.


To add to this, since water is the solvent, it will be in excess and so its concentration will not experience a significant change. This is why when water is in its liquid form, we don't include it in the K expression.

Ying Yan 1F
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Joined: Fri Aug 02, 2019 12:16 am

Re: Water in K constant

Postby Ying Yan 1F » Thu Jan 23, 2020 12:48 pm

If water is in its gas phase in the reaction, then you do include it in your equilibrium ratio.

Simon Dionson 4I
Posts: 107
Joined: Sat Sep 14, 2019 12:17 am

Re: Water in K constant

Postby Simon Dionson 4I » Thu Jan 23, 2020 12:51 pm

Water is only not included if it is a solvent (liquid) or a solid.
Last edited by Simon Dionson 4I on Thu Jan 23, 2020 1:16 pm, edited 1 time in total.

Shivam Rana 1D
Posts: 106
Joined: Fri Aug 09, 2019 12:16 am

Re: Water in K constant

Postby Shivam Rana 1D » Thu Jan 23, 2020 12:51 pm

water is included in the Kp expression if it is a vapor.


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