Not including solids and liquids

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Erik Buetow 1F
Posts: 96
Joined: Fri Aug 30, 2019 12:15 am

Not including solids and liquids

Postby Erik Buetow 1F » Sun Jan 19, 2020 8:14 pm

Are solids and liquids always negated in calculations dealing with equilibrium constants? And if so, why?

TarynD_1I
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

Re: Not including solids and liquids

Postby TarynD_1I » Sun Jan 19, 2020 8:17 pm

Solids and liquids are not used in calculating an equilibrium constant, only gasses and aqueous solutions are considered. This is because the activity of the pure solids and liquids are considered to be 1, so it would not affect the equilibrium equation (their concentrations do not change throughout the experiment).

Isabella Dal Porto 1H
Posts: 100
Joined: Fri Aug 30, 2019 12:16 am

Re: Not including solids and liquids

Postby Isabella Dal Porto 1H » Sun Jan 19, 2020 8:28 pm

The activity of a pure solid or liquid is equal to 1 so it doesn't affect the value of the equilibrium constant.

Sydney Pell 2E
Posts: 100
Joined: Wed Sep 11, 2019 12:17 am

Re: Not including solids and liquids

Postby Sydney Pell 2E » Sun Jan 19, 2020 8:41 pm

K is calculated with the concentration of the products over the concentration of the reactants at equilibrium. Since solids and liquids in a reaction do not change concentrations, they would just cancel out when calculating the equilibrium constant. So, only gases are considered when calculating K.

MeeraBhagat
Posts: 95
Joined: Sat Aug 24, 2019 12:15 am

Re: Not including solids and liquids

Postby MeeraBhagat » Sun Jan 19, 2020 8:51 pm

Solids and liquids are not included in the equilibrium constant equation because they do not have concentrations. They have densities. Therefore, they are negated when calculating the K value.

Chris Charton 1B
Posts: 69
Joined: Mon Jun 17, 2019 7:23 am

Re: Not including solids and liquids

Postby Chris Charton 1B » Sun Jan 19, 2020 8:53 pm

Pure liquids and solids have an activity level of 1, and thus do not need to be included in equilibrium equations.

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

Re: Not including solids and liquids

Postby CalvinTNguyen2D » Sun Jan 19, 2020 9:17 pm

Solids and liquids do not affect the equilibrium in any significant way, and are not measured in concentrations; as a result, they are left out in K value calculations.

Anna Chen 1K
Posts: 104
Joined: Thu Jul 25, 2019 12:18 am

Re: Not including solids and liquids

Postby Anna Chen 1K » Sun Jan 19, 2020 9:55 pm

Solids and liquids equal 1 so they are neglected when calculating K.


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