Answer to Question #89897 in General Chemistry for Kyle O'Neill

Question

What is the pH of 0.00028 M KOH? Is this solution acidic, basic, or neutral?

Answer 1

$[KOH]=[OH-]=0.00028 mol/L$

$[H3O+][OH-]=Kw$

$[H3O+]=Kw/[OH-]=1* 10^{-14}/0.00028=3.57*10^{-11}$

$pH=-log[H3O+]=-log(3.57*10^{-11})=-10.45$

It is basic solution