(10) What is the pH of the solution after adding the 10 mL of KOH?
Since some of the acid has been neutralized, it is expected that the pH will be higher than that of the original solution (but still in the acidic range). First, the number of moles of hydronium ions must be calculated. The left side of equation (5) gives an expression for the number of moles present after the addition of the KOH. When substituting in for x , the result is
The total volume of the solution is now 60 mL. The acid concentration, and thus the hydronium concentration, is now