Clarification on pKw
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Clarification on pKw
Hello, I need some clarification on the meaning of pKw, and I was wondering if pKw is supposed to always equal 14 or is it like other K values that can be different depending on the equilibrium question at hand?
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Re: Clarification on pKw
Kw is the equilibrium constant for autoprotolysis of water and represents the fact that the concentration of hydronium ions times the concentration of hydroxide ions will always equal 1.0 * 10-14. pKw is the negative log base 10 of Kw, so yes, it always equals 14, whether a solution is basic or acidic.
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Re: Clarification on pKw
This only holds true at 25 degrees celsius and 1 atm just like with K, because remember that temperature is the only thing that can change the equilibrium constant. In this class however, pkw has always been 14. Hope that clarifies!
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Re: Clarification on pKw
At 25 degrees C (standard temp) pKw will always be 14. That said, the pK value of a reaction can change when a temperature change occurs.
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Re: Clarification on pKw
Kw is the equilibrium constant for the autoprotolysis reaction of water and it equals 10^-14 at 25 degrees Celsius (298 K) "p" is the shorthand for "- log" (negative log base 10), so pKw would be equal to 14 at 298 K. I remember Dr. Lavelle mentioning that even if the temperature is changed, Kw roughly stays around 10^-14.
Hope this helps!
Hope this helps!
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Re: Clarification on pKw
yeah Pkw is basically the total possible Ph or ph of 14 which is usually Pha x Phb.
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Re: Clarification on pKw
Kw is the concentration of H3O+ multiplied by the concentration of OH-. pKw is when you take the negative logarithm of Kw.
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Re: Clarification on pKw
PKW is a constant that relates the forward and reverse reactions of acids and bases. Just think of it as a constant that facilitates finding either pKa or pKb given either one.
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Re: Clarification on pKw
I believe that for water at a standard temperature of 25 C, the pKw will remain 14 but changing these parameters could also change the constant, such as a different temperature or different liquid other than water.
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