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### solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 4:19 pm
Are solids included in the calculation for the equilibrium constant when using partial pressure?

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 4:35 pm
No, pure solids and liquids are excluded in the calculation

### Re: solids in calculating equilibrium constant?  [ENDORSED]

Posted: Sun Jan 13, 2019 4:45 pm
As Dr. Lavelle said,

Molar concentration of a pure substance (solid or liquid) does not change in a reaction
∴ solids and liquids are not included in K expression

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 4:46 pm
Pure solids and liquids are not included in calculating the equilibrium constant, but aqueous solutions and gases are included.

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 4:49 pm
only aq and g solutions are included in the equation (and g is in partial pressure)

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 5:11 pm
No, only aqueous solutions and gases are included in calculating the equilibrium constant.

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 6:18 pm
Edward Suarez 1I wrote:only aq and g solutions are included in the equation (and g is in partial pressure)

It should also be expanded that when reactions are completed in a fixed volume container, the addition of noble (inert) gases does not affect equilibrium for similar reasons as pure solids and liquids: they do not affect the concentration of reactant/product.

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 8:56 pm
Does anyone know why they are not included or is it not necessary to know why?

### Re: solids in calculating equilibrium constant?

Posted: Sun Jan 13, 2019 11:57 pm
Solids and liquids are NOT included when calculating the equilibrium constant because a solids concentration would be 100% which is just 1 and doesn't affect the answer.
Only aqueous solutions and gases are included in the calculation of the equilibrium constant.