<span>it tells you the sequence in which events occurred, not how long ago they occurred.</span>
For example <span>in chemistry, a solution is a homogeneous
mixture composed of two or more substances. In such a mixture, a solute
is a substance dissolved in another substance, known as a solvent.</span>
POH will be -log[conc of OH]
-log (3.9E-08) = 7.409
pH = 14- pOH
pH = 14 - 7.409
pH = 6.59