Question #231e7

1 Answer
Aug 3, 2017

#["H"_3"O"^+] = 1.1xx10^-13# #M#

Explanation:

We're asked to find the hydronium ion concentration #["H"_3"O"^+]#, given the hydroxide ion concentration #["OH"^(-)]#.

At #25# #""^"o""C"#, we have the relationship

#ul(K_w = ["OH"^(-)]["H"_3"O"^+] = 1.00xx10^-14color(white)(l)M^2#

Since #["OH"^- ]# is given as

#9.0xx10^-2# #M#

we plug that into the equation and solve for #["H"_3"O"^+]#:

#["H"_3"O"^+] = (1.00xx10^-14color(white)(l)M^2)/(9.0xx10^-2color(white)(l)M) = color(red)(ulbar(|stackrel(" ")(" "1.1xx10^-13color(white)(l)M" ")|)#

rounded to #2# significant figures.