Final answer:
To find the pH during a strong acid-strong base titration, one must consider reactant concentrations and volumes. At the equivalence point, the pH will be neutral, but prior to that, the pH is determined by the excess strong acid or base. Calculations involve moles of reactants and the degree of neutralization.
Step-by-step explanation:
The student is asking how to calculate the pH of a solution during a titration process between a strong base (KOH) and a strong acid (HCl). Titration is an analytical technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. The pH calculation during titration depends on the volumes and concentrations of the reactants as well as the point in the titration process.
For example, at the equivalence point of a strong acid-strong base titration, the pH should be neutral (pH = 7) since the moles of acid and base will be equal and will completely neutralize each other. However, before reaching the equivalence point, the pH can be calculated based on the amount of excess strong base or strong acid present in the solution.
In the specific question asked by the student, they must use the molarity (M) and volume (mL) of the KOH and HCl solutions to determine how many moles of each reactant are present and how many of those moles have reacted. This will allow the student to calculate the remaining concentration of the hydroxide or hydronium ions in the solution and thus, the pH. Note that in strong acid-strong base titrations, we can assume that KOH and HCl ionize completely in solution.