Chemistry........

Question

An aqueous solution at 25°C

 has a H3O+

 concentration of ×2.610−9M

. Calculate the OH−

 concentration. Be sure your answer has 2 significant digits. 

Answer 1

At 25ºC Kw = 1x10^-14 = [H⁺][OH^-]

1.0x10^-14/2.61x10^-9 = 3.83x10^-6 M OH^- = 3.8x10^-6 M (2 sig. figs.)