K expression involving solids/liquids

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Zaynab Hashm 2I
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K expression involving solids/liquids

Postby Zaynab Hashm 2I » Fri Jan 10, 2020 2:58 pm

why do we not include the concentrations of solids or liquids in the equilibrium constant expression, k?

* do we only account for concentrations in the aqueous state?

Emily Chirila 2E
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Joined: Sat Jul 20, 2019 12:16 am

Re: K expression involving solids/liquids

Postby Emily Chirila 2E » Fri Jan 10, 2020 3:07 pm

We only use gases and aqueous solutions in K expressions. Solids don't have concentrations so they are not included and pure substances (liquids) will not react enough to make any effect so they are left out as well.

Alex Tchekanov Dis 2k
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Re: K expression involving solids/liquids

Postby Alex Tchekanov Dis 2k » Fri Jan 10, 2020 3:32 pm

We don't include solids or liquids because, in the grand scheme of the reaction, only a negligible amount is used and therefore doesn't affect the equilibrium constant.

Katie Kyan 2K
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Re: K expression involving solids/liquids

Postby Katie Kyan 2K » Fri Jan 10, 2020 4:06 pm

When writing the equilibrium constant expression we don't include solids and liquids because, as Dr. Lavelle said in class, the molar concentration of a pure substance doesn't change in a reaction and thus, does not need to be included.

Hannah Pham
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Re: K expression involving solids/liquids

Postby Hannah Pham » Fri Jan 10, 2020 4:09 pm

To determine the equilibrium constant, only gases and aqueous solutions are used. Liquids and solids are not used because pure substances do not change in a reaction.

Connor Chappell 2B
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Re: K expression involving solids/liquids

Postby Connor Chappell 2B » Fri Jan 10, 2020 5:22 pm

The concentration of liquids (solutes) and solids are not included in the calculation of the equilibrium constant because of the inability to apply this characteristic to these phenomena and have it possess and plausible meaning. Solutes, in a reaction at equilibrium, have an insignificant change in concentration, so it is safe to approximate the true value of K and leave out the solute. Solids are excluded because solids do not have a concentration fundamentally.

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

Re: K expression involving solids/liquids

Postby Ying Yan 1F » Fri Jan 10, 2020 5:30 pm

Solid and pure liquids cannot really react effectively with other substances and doesn't have a concentratio, therefore they are not included in the equilibrium constant equation.

Edmund Zhi 2B
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Joined: Sat Jul 20, 2019 12:16 am

Re: K expression involving solids/liquids

Postby Edmund Zhi 2B » Fri Jan 10, 2020 5:35 pm

Pure substances do not have concentrations and do not impact equilibrium constants because they have no concentration that changes in the reaction


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