Question

What is the pH of a solution with [OH-]= (9.00x10^-4)? Enter your answer in scientific notation and with three signigicant figures?

Answer 1

Hey there!:

Given [ OH⁻ ] = 9.00 x 10⁻⁴

We know that : [H⁺ ] [OH⁻ ] = 1 x 10⁻¹⁴

Thus [H⁺ ] =  ( 1 x 10⁻¹⁴ ) / ( 9.00 x 10⁻⁴ )

[ H⁺ ] = 1 x 10⁻¹¹ M

therefore:

pH = - log [ H⁺ ]

pH = - log [ 1 x 10⁻¹¹ ]

pH = 10.95

Therfore pH = 10.95

I hope this will help !