15.3 pH-A Measure Of Acidity

Question 1

Define pH. Why do chemist normally choose to discuss the acidity of a solution in terms of pH rather than hydrogen in M, [H+]?

Answer 1

The pH of a solution is defined as the negative logarithm of the [H+] in mol/L

pH=-log[H+]

The M of hydrogen ions and hydroxyl ions are usually very small numbers. As they are invoice the to work with, pH scale is used as a more practical measure

Question 2

Define pOH. Write the equation relating pH and pOH

Answer 2

A negative logarithm of M of ions in mol/L

pOH=-log[OH-]