Chapter 14, Problem 124DIA

Data Interpretation and Analysis

The progress of an acid-base titration can be monitored by measuring the pH of the solution being titrated while adding base. The resulting graph, called a titration curve, is a plot of the pH versus the volume of added base. The graph shown here is the titration curve for an unknown monoprotic acid (HX) titrated with 0.100 M NaOH. Examine the graph and answer the questions that follow.

(a) Write an equation for the neutralization reaction that occurs during the titration.

(b) Why does the pH of the solution increase during the course of the titration?

(c) The equivalence point of the titration occurs at the point where the titration curve is the steepest. What is the pH equivalence point? What is the pH halfway to the equivalence point?

(d) Determine the number of moles of the acid HX that were present in the solution that was titrated.