Clarification on pKw

[Bronson Mathos 1H]

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?

[Ryan Hoang 1D]

At standard temperature, pKw should always equal 14, and Kw=10^-14!

[Leo Naylor 2F]

K_w 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. pK_w is the negative log base 10 of K_w, so yes, it always equals 14, whether a solution is basic or acidic.

[Sara_Lim_2C]

From my knowledge pKw is always 14 at 25C.

[Giselle Granda 3F]

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!

[Hannah Lechtzin 1K]

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.

[Can Yilgor 2D]

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!

[Javier Perez M 1H]

yeah Pkw is basically the total possible Ph or ph of 14 which is usually Pha x Phb.

[Lauren Sarigumba 1K]

Kw is the concentration of H3O+ multiplied by the concentration of OH-. pKw is when you take the negative logarithm of Kw.

[Sam Wentzel 1F 14B]

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.

[Mansi Solanki 3A]

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.

[Mehreen 3I]

pKa will always be 14 at 25 C.

[kristinalaudis3e]

pKw will always be 14 because it is a constant!

[LovepreetSran_3H]

At 25 degrees Celsius pKw will always be equal to 14

[David Y]

Kw should be 10^-14 which would be used in the calculation.

[George Hernandez 3I]

Speaking on STP, yes the Kw is always 14