This is basic chemistry btw.
screen shoted it

Water ionizes by the equation h2o(l)⇌h+(aq)+oh−(aq) the extent of the reaction is small in pure water and dilute aqueous solutions. this reaction creates the following relationship between [h+] and [oh−]: kw=[h+][oh−] keep in mind that, like all equilibrium constants, the value of kw changes with temperature.

Measuring which physical property is most likely to produce the most precise results when trying to identify a substance

Electrons are extremely important to what area of technology? a) anti-aging research b) household product development c) electronics d) drug discovery