Fundamentals of Chemistry
DOE-HDBK-1015/1-93
ACIDS, BASES, SALTS, AND pH
Rev. 0
CH-01
Page 49
Example 1:
The hydrogen concentration, [H ], of a solution is 4.8 x 10 moles/liter. What
+
-8
is the pH of the solution?
Solution 1:
Example 2:
The pH of a solution is 3.83. What is the hydrogen concentration of the
solution?
Solution 2:
pOH
It is also important to understand the relationship between the [H ] and the [OH ]
+
-
concentrations. The pOH of a solution is defined as the negative logarithm of the hydroxyl
concentration, represented as [OH ] in moles/liter.
-
pOH = -log [OH ]
(1-3)
-
[OH ] = 10
(1-4)
-
-pOH
For water solutions, the product of the hydrogen ion concentration and the hydroxyl
concentration is always 1 x 10 at 25?C. This means that the sum of pH and pOH is equal to
-14
14 under these conditions.
[H ] x [OH ]
= 1 x 10
+
-
-14
pH + pOH
= 14
The following example illustrates this point.
