1) An unlabeled laboratory solution is found to contain a H+ ion concentration of 1 x 10-4 M. What is the OH concentration, [OH-], in the solution?
A) 1 x 10-18 M.
B) 1x 10-14 M.
C) 1 x 10-10 M
D) 1x 10-7 M

C) 1 x 10-10 M

Explanation:

To solve this question we must use the equation:

Kw = [H+] [OH-]

Where Kw is the equilibrium dissociation of water = 1x10-14

[H+] is the molar concentration of hydronium ion = 1x10-4M

[OH-] is the molar concentration of hydroxyl ion

Replacing:

1x10-14= 1x10-4 [OH-]

[OH-] = 1x10-14 / 1x10-4M

[OH-] = 1x10-10 M

Right option is: