pH = [H+] [OH-]

[Tiahna Thomas 2C]

From a conceptual perspective, can someone explain why the concentrations of H+ and OH- multiplied together equals the pH? Thank you!

[Ella Henrickson 3I]

I'm slightly confused by your question, but multiplying [H+]*[OH-] gives 1 x 10^-14 which is the equilibrium constant for water (k_w). This equation is just helpful for getting the [OH-] concentration from [H+] and vice versa.

- it is also always mentioned that k_w = 1 x 10^-14 at 25 degrees Celsius, which seems like it will be important later.

[Raizel Ferrer 1H]

I agree with what the previous post said. The concentrations of [H+] and [OH-] multiplied together equals 10^-14 @ 25 degrees celsius in water which is the dissociation constant. There are other equations to find the pH as well by using pH+OH = 14 and pH = -log[H+].

[Aida Fraser 2I]

also [H+] [OH-] multiplied together equals 10^-14 makes sense mathematically due to the fact that pOH + pH = 14