Biochemistry at The Biology Project

Acids & Bases Problem Set

Question 6: Relation between H + and OH - concentrations

Tutorial to help answer the question

If the concentration of H +  in a solution is 10 - 3 M, what will the concentration of OH -  be in the same solution at 25° C?

A. 10 - 3 M
B. 10 - 11 M
C. 1011 M
D. 2 x 10 - 11 M
E. 10 - 14 M

Tutorial

Relation between H + and OH -  concentrations at 25° C
In aqueous solutions at 25° C, the product of the H +  and OH -  concentrations is always 10 - 14, as expressed in this equation:

[H +] [OH - ] = 10 - 14

This allows calculation of the OH -  concentration if the H +  concentration is known.

[OH - ] = 10 - 14 / [H +]

[OH - ] = 10 - 14 / 10 - 3 = 10 - 11

This calculation is used when the solution in question is not pure water, but contains some mixture of acids and bases.

[Problem 6] [Answer] [Problem 7]

[MAINPAGE] [Biochemistry] [Vocabulary] The Biology Project


The Biology Project
Department of Biochemistry and Molecular Biophysics

The University of Arizona
January 6, 1999
Revised: October 2004
Contact the Development Team

http://www.biology.arizona.edu
All contents copyright © 1999. All rights reserved.

The Biology Project Biochemistry