## Kw Equations

Drew Myers 4G
Posts: 100
Joined: Sat Aug 17, 2019 12:17 am

### Kw Equations

What are the equations that are equivalent to Kw (1.0 x 10^-14)?

Ruby Tang 2J
Posts: 102
Joined: Fri Aug 30, 2019 12:15 am

### Re: Kw Equations

[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)

Emily Lo 1J
Posts: 50
Joined: Thu Sep 19, 2019 12:16 am

### Re: Kw Equations

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.

peteryim
Posts: 54
Joined: Sat Sep 07, 2019 12:17 am

### Re: Kw Equations

Also, keep in mind that although:

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

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

zfinn
Posts: 106
Joined: Fri Aug 30, 2019 12:16 am

### Re: Kw Equations

[h3o+][oh-]=Kw and [Ka][Kb]=Kw

Micah3J
Posts: 100
Joined: Tue Oct 08, 2019 12:16 am

### Re: Kw Equations

there is also pkw = pka + pkb

ABombino_2J
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

### Re: Kw Equations

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.

Gabriel Ordonez 2K
Posts: 113
Joined: Sat Jul 20, 2019 12:15 am

### Re: Kw Equations

Kw=ka x kb

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

Nick Lewis 4F
Posts: 111
Joined: Wed Sep 18, 2019 12:18 am

### Re: Kw Equations

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.

Ayushi2011
Posts: 101
Joined: Wed Feb 27, 2019 12:17 am

### Re: Kw Equations

[h3O+] + [OH-] = kw = 1x10^-14

Mai V 4L
Posts: 111
Joined: Fri Sep 28, 2018 12:23 am

### Re: Kw Equations

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!!