I need help within the next hour. Help please!

Question

Calculate the [OH-] in a solution with a pH of 12.9 must use decimals



Answer 1

There are several approaches to this problem, but I will give you one of them.

pH is defined as the negative logarithm of the hydrogen ion concentration or pH = - log [H+]. To get the [H+] you must calculate the antilog of - pH or - 12.9 using your calculator. You should get [H+] = 1.26 x 10^-13M.

Next you need to calculate the [OH-] concentration using the [H+] you just calculated.

You must use the fact that the [H+] x [OH-] = 10^-14. Solving for [OH-] = 10^-14 / 1.26 x 10^-13 = 0.079 M.