## Why is Kw value typically used at 25 degrees C [ENDORSED]

Acidity $K_{a}$
Basicity $K_{b}$
The Conjugate Seesaw $K_{a}\times K_{b}=K_{w}$

peytonruiz 1H
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### Why is Kw value typically used at 25 degrees C

Why is it standard to use the value for Kw at 25 degrees C?

Maeve Gallagher 1J
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### Re: Why is Kw value typically used at 25 degrees C

25 degrees Celsius is the standard room temperature value used for most equations and calculations in chemistry. It is just used to show that its not super hot or super cold.

Yizhou Liu 3L
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### Re: Why is Kw value typically used at 25 degrees C

Because 25 degrees C is the room temperature. If the temperature increase, the Kw will increase as well.

Wayland Leung
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### Re: Why is Kw value typically used at 25 degrees C

Does only changing the temperature affect the Kw value? Does anything else affect the Kw value?

Dylan Davisson 2B
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### Re: Why is Kw value typically used at 25 degrees C

Because kW is the equilibrium constant, it only changes with temperature. This is because the dissociation of water molecules is an endothermic process, a process that is affected by temperature. The higher the temperature, the further the equilibrium moves to the right, which affects the kW value.

diangelosoriano
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### Re: Why is Kw value typically used at 25 degrees C

Will we be expected to be able to calculate at different temperatures for the final?

Chem_Mod
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### Re: Why is Kw value typically used at 25 degrees C  [ENDORSED]

diangelosoriano wrote:Will we be expected to be able to calculate at different temperatures for the final?

Chem 14A, no.

I will cover this in Chem 14B when we do thermodynamics.