144 13- 12. 11 Titration of Weak Acid 10- 9 86 7. Equivalence point pH, 8.72 65 A 4 3- 210 0001-0 to nojuan anta 0 5 10 15 20 25 30 35 40 45 50 Volume of 0.100 M NaOH added (mL) Fig. 10.2: Titration curve of a weak acid with a strong base The shape of a titration curve depends on the ionization constants of the acid and base and their concentrations. The example given above is for a weak acid and strong base. The equivalence point is defined as the point where the amount of base added is equal to the original amount of acid in the solution. Therefore, at the equivalence point, the number of moles of base added equals the number of moles of acid originally present in the solution being titrated. After determining the equivalence point, the concentration of the basic solution can be easily calculated with the titration formula (when the stoichiometry of acid and base is 1:1): Molarity of acid (mol/L) x Volume of acid = Molarity of base (mol/L) x Volume of base Macid X Vacid = Mbase X Vbase moles of acid in original solution = moles of base added Concentration of base (mol/L) or [base] = [moles of acid in original solution] (volume in L of base at equivalence point)

144 13- 12. 11 Titration of Weak Acid 10- 9 86 7. Equivalence point pH, 8.72 65 A 4 3- 210 0001-0 to nojuan anta 0 5 10 15 20 25 30 35 40 45 50 Volume of 0.100 M NaOH added (mL) Fig. 10.2: Titration curve of a weak acid with a strong base The shape of a titration curve depends on the ionization constants of the acid and base and their concentrations. The example given above is for a weak acid and strong base. The equivalence point is defined as the point where the amount of base added is equal to the original amount of acid in the solution. Therefore, at the equivalence point, the number of moles of base added equals the number of moles of acid originally present in the solution being titrated. After determining the equivalence point, the concentration of the basic solution can be easily calculated with the titration formula (when the stoichiometry of acid and base is 1:1): Molarity of acid (mol/L) x Volume of acid = Molarity of base (mol/L) x Volume of base Macid X Vacid = Mbase X Vbase moles of acid in original solution = moles of base added Concentration of base (mol/L) or [base] = [moles of acid in original solution] (volume in L of base at equivalence point)

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter16: Reactions Between Acids And Bases

Section: Chapter Questions

Problem 16.58QE

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Similar questions

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