For example, K for ethanoic acid = 1.76
Hence pK =
pK is a measure of the strength of acids. The smaller the value of pK the stronger the acid.
Some examples of K and pK values for acids are shown in Table 4.2
Acid Relative strength = acid becomes stronger
Example 4.1
The K for a weak monobasic acid is 1.0 x 10. In a 0.1 mol dm solution of the acid, calculate
(a) The concentration of H ions and
(b) The concentration of OH ions.