Textbook Question
Predict whether the equivalence point of each of the following titrations is below, above, or at pH 7: (b) calcium hydroxide titrated with perchloric acid.
Ch.17 - Additional Aspects of Aqueous Equilibria
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch.1 - Introduction: Matter, Energy, and Measurement177
- Ch.2 - Atoms, Molecules, and Ions231
- Ch.3 - Chemical Reactions and Reaction Stoichiometry216
- Ch.4 - Reactions in Aqueous Solution189
- Ch.5 - Thermochemistry175
- Ch.6 - Electronic Structure of Atoms168
- Ch.7 - Periodic Properties of the Elements150
- Ch.8 - Basic Concepts of Chemical Bonding177
- Ch.9 - Molecular Geometry and Bonding Theories200
- Ch.10 - Gases179
- Ch.11 - Liquids and Intermolecular Forces113
- Ch.12 - Solids and Modern Materials154
- Ch.13 - Properties of Solutions157
- Ch.14 - Chemical Kinetics199
- Ch.15 - Chemical Equilibrium128
- Ch.16 - Acid-Base Equilibria164
- Ch.17 - Additional Aspects of Aqueous Equilibria163
- Ch.18 - Chemistry of the Environment105
- Ch.19 - Chemical Thermodynamics164
- Ch.20 - Electrochemistry171
- Ch.21 - Nuclear Chemistry122
- Ch.22 - Chemistry of the Nonmetals82
- Ch.23 - Transition Metals and Coordination Chemistry79
- Ch.24 - The Chemistry of Life: Organic and Biological Chemistry16
Brown14th EditionChemistry: The Central ScienceISBN: 9780134414232Not the one you use?Change textbook
Chapter 17, Problem 37a,c
Predict whether the equivalence point of each of the following titrations is below, above, or at pH 7: (a) NaHCO3 titrated with NaOH (c) KOH titrated with HBr.
Verified step by step guidance1
Identify the nature of the acid and base involved in each titration. For (a) NaHCO3 titrated with NaOH, NaHCO3 is a weak acid (bicarbonate ion) and NaOH is a strong base. For (c) KOH titrated with HBr, KOH is a strong base and HBr is a strong acid.
Understand the concept of equivalence point: It is the point in a titration where the amount of titrant added is enough to completely neutralize the analyte solution. The pH at the equivalence point depends on the strength of the acid and base involved.
For (a) NaHCO3 titrated with NaOH: Since NaHCO3 is a weak acid and NaOH is a strong base, the equivalence point will be above pH 7. This is because the conjugate base of the weak acid (carbonate ion) will hydrolyze to form a basic solution.
For (c) KOH titrated with HBr: Both KOH and HBr are strong, so the equivalence point will be at pH 7. This is because the neutralization of a strong acid with a strong base results in a neutral solution.
Summarize the results: (a) The equivalence point is above pH 7 due to the weak acid and strong base. (c) The equivalence point is at pH 7 due to the strong acid and strong base.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Acid-Base Titration
An acid-base titration is a quantitative analytical method used to determine the concentration of an acid or base in a solution. During the titration, a solution of known concentration (the titrant) is added to a solution of unknown concentration until the reaction reaches the equivalence point, where the amount of acid equals the amount of base. The pH at this point can vary depending on the nature of the acid and base involved.
Recommended video:
Guided course
03:04
Acid-Base Titration
Equivalence Point and pH
The equivalence point in a titration is the stage at which the amount of titrant added is stoichiometrically equivalent to the amount of substance in the sample solution. The pH at the equivalence point is influenced by the strength of the acid and base being titrated. Strong acid-strong base titrations typically have an equivalence point at pH 7, while weak acid-strong base or strong acid-weak base titrations can result in equivalence points that are below or above pH 7, respectively.
Recommended video:
Guided course
07:28pH at the Equivalence Point Example
Buffer Solutions
Buffer solutions are mixtures that can resist changes in pH upon the addition of small amounts of acid or base. In the case of NaHCO3 (sodium bicarbonate), it acts as a weak acid and can form a buffer system with its conjugate base, Na2CO3. This buffering capacity affects the pH during titration, particularly around the equivalence point, leading to a pH that may be above or below 7 depending on the titrant used.
Recommended video:
Guided course
03:02Buffer Solutions
Related Practice
Textbook Question
The samples of nitric and acetic acids shown here are both titrated with a 0.100 M solution of NaOH(aq).
Determine whether each of the following statements concerning these titrations is true or false. (a) A larger volume of NaOH1aq2 is needed to reach the equivalence point in the titration of HNO3.
Textbook Question
Determine whether each of the following statements concerning the titrations in Problem 17.35 is true or false. (a) The pH at the beginning of the two titrations will be the same.
Textbook Question
Determine whether each of the following statements concerning the titrations in Problem 17.35 is true or false. (b) The titration curves will both be essentially the same after passing the equivalence point.
Textbook Question
Predict whether the equivalence point of each of the following titrations is below, above, or at pH 7: (b) NH3 titrated with HCl.
Textbook Question
Predict whether the equivalence point of each of the following titrations is below, above, or at pH 7: (a) formic acid titrated with NaOH.