A student peforms a titration, titrating 25.00 mL of a weak monoprotic acid, HA, with a 1.15 M solution of NaOH. They collect data, plot a titration curve and determine the values given in the below table. ml NaOH added pH Half-way Point 17.72 3.31 Equivalence point 35.44 8.37 How many moles of NaOH have been added at the equivalence point? mol What is the total volume of the solution at the equivalence point? mL During the titration the following reaction occurs HA + NaOH = NaA + H2O What is the concentration of A (the conjugate base of the weak acid) at the equivalence point? Use [A]and the pH at the equivalence point to estimate Ka of the weak acid (this is the hard way of estimating Ka) Use the pH at the half-way point to estimate Ką of the weak acid (this is the easier way)

A student peforms a titration, titrating 25.00 mL of a weak monoprotic acid, HA, with a 1.15 M solution of NaOH. They collect data, plot a titration curve and determine the values given in the below table. ml NaOH added pH Half-way Point 17.72 3.31 Equivalence point 35.44 8.37 How many moles of NaOH have been added at the equivalence point? mol What is the total volume of the solution at the equivalence point? mL During the titration the following reaction occurs HA + NaOH = NaA + H2O What is the concentration of A (the conjugate base of the weak acid) at the equivalence point? Use [A]and the pH at the equivalence point to estimate Ka of the weak acid (this is the hard way of estimating Ka) Use the pH at the half-way point to estimate Ką of the weak acid (this is the easier way)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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