Solids and Liquids

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

Solids and Liquids

Postby Erik Buetow 1F » Sun Jan 12, 2020 11:09 am

I don’t totally understand why the solids and liquids in a reaction are not used in the calculations??

SnehinRajkumar1L
Posts: 101
Joined: Thu Jul 11, 2019 12:15 am

Re: Solids and Liquids

Postby SnehinRajkumar1L » Sun Jan 12, 2020 11:10 am

Solids and liquids are typically in excess and thus tend to not change much in equilibrium.

Jamie Lee 1F
Posts: 106
Joined: Fri Aug 09, 2019 12:16 am

Re: Solids and Liquids

Postby Jamie Lee 1F » Sun Jan 12, 2020 11:22 am

Their concentrations usually do not change during reaction, whereas gaseous and aqueous solutions do. In order for concentration to change, something must dissolve in something else; liquids and solids don't dissolve and therefore aren't taken into account in equilibrium calculations.

Hope Hyland 2D
Posts: 50
Joined: Wed Feb 20, 2019 12:16 am

Re: Solids and Liquids

Postby Hope Hyland 2D » Sun Jan 12, 2020 9:04 pm

Solids and liquids typically don't change concentrations at all during reactions, so they are not included in the equilibrium constant.

Mulin_Li_2J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

Re: Solids and Liquids

Postby Mulin_Li_2J » Sun Jan 12, 2020 9:23 pm

Since we use concentrations to approximate chemical activities of reactants and products, we can also use chemical activities directly instead. And because chemical activities of solvent and solid both equal to one so they exert no effect on the value of K. Thus, we can just simply ignore solid and solvent when calculating K and plug in only concentration of gases and solutes.

Sjeffrey_1C
Posts: 108
Joined: Wed Feb 20, 2019 12:17 am

Re: Solids and Liquids

Postby Sjeffrey_1C » Sun Jan 12, 2020 9:24 pm

Liquids and solids are essentially incompressible, unlike gas, which is compressible.

505306205
Posts: 97
Joined: Thu Jul 25, 2019 12:15 am

Re: Solids and Liquids

Postby 505306205 » Sun Jan 12, 2020 9:26 pm

Solids are not used because you cannot measure the concentration of solids. Liquids are not used because pure liquids are too dilute to affect the K.


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