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Kw Equations

Posted: Sun Jan 26, 2020 1:19 pm
by Drew Myers 4G
What are the equations that are equivalent to Kw (1.0 x 10^-14)?

Re: Kw Equations

Posted: Sun Jan 26, 2020 1:28 pm
by Ruby Tang 2J
[H3O+][OH-] = Kw, and [Ka][Kb] = Kw. Keep in mind however that Kw will be different depending on temperature. We just tend to use 1*10^-14 b/c this is what Kw is equal to at the standard state temperature (25C)

Re: Kw Equations

Posted: Sun Jan 26, 2020 4:14 pm
by Emily Lo 1J
The equation is [H3O^+][OH^-] = Kw. Generally, it would be [1.0x10^-7][1.0x10^-7] = 1.0x10^-14. This is when Kw is at 25 C., otherwise I think the Kw value would be different at different temperatures.

Re: Kw Equations

Posted: Sun Jan 26, 2020 5:19 pm
by peteryim
Also, keep in mind that although:

[Ka][Kb] = Kw and [H3O+][OH-] = Kw

[Ka] != [H3O+] and [Kb] != [OH-]

Re: Kw Equations

Posted: Sun Jan 26, 2020 6:04 pm
by zfinn
[h3o+][oh-]=Kw and [Ka][Kb]=Kw

Re: Kw Equations

Posted: Sun Jan 26, 2020 6:07 pm
by Micah3J
there is also pkw = pka + pkb

Re: Kw Equations

Posted: Sun Jan 26, 2020 11:23 pm
by ABombino_2J
ka*kb=kw=10^-14
pka+pka=pkw=14 (you get this by taking the -log of the first equation)
Also, these equations are on the equation sheet just replace [H3O+] with ka, [OH-] with kb, pH with pka, and POH with pkb.

Re: Kw Equations

Posted: Sun Jan 26, 2020 11:26 pm
by Gabriel Ordonez 2K
Kw=ka x kb

Kw=10^-14=(1.0x10^-7)(1.0x10^-7)

Re: Kw Equations

Posted: Sun Jan 26, 2020 11:28 pm
by Nick Lewis 4F
Pretty much this is a way of saying that pH + pOH = 14, but it is showing it in terms of the concentrations of [H30+] and [OH-]. I know these equations are usually always given on the equation sheet, so u can deduce subsequent equations from it.

Re: Kw Equations

Posted: Thu Jan 30, 2020 4:01 pm
by Ayushi2011
[h3O+] + [OH-] = kw = 1x10^-14

Re: Kw Equations

Posted: Sun Mar 08, 2020 11:15 pm
by Mai V 4L
Hi does anyone have a preferred online resource/chart they like to refer to for studying this topic? Like khan academy or a youtube video or something thanks!!