Chemistry the Central Science 13th Edition Custom for Lamar University
Chemistry the Central Science 13th Edition Custom for Lamar University
13th Edition
ISBN: 9781269962667
Author: Theodore L. Brown, H. Eugene LeMay Jr., Bruce E. Bursten, Batherine J. Murphy, Patrick M. Woodward, Matthew W. Stoltzfus
Publisher: Pearson Learning Center
bartleby

Concept explainers

Question
Book Icon
Chapter 17, Problem 1DE

(a)

Interpretation Introduction

To determine: A set of experiments or calculations to test the given hypotheses.

Concept Introduction: The replacement of the hydrogen atom by chlorine in the methyl group of the acetic acid increases the polarity of the OH bond and chlorine group stabilizes the carboxylate ion formed after the donation of the proton and, hence increasing the acidity.

As the pKa of the acid lowers, the acid becomes stronger and hence its solubility in the low pH solution increases. The weaker is the acid, the higher is its pKa and the lower is it solubility in acidic solution.

(a)

Expert Solution
Check Mark

Answer to Problem 1DE

Solution: Due to the presence of chlorine atom, the acidity of trichloroacetic acid is more than that of chloroacetic acid and acetic acid.

Explanation of Solution

The pKa of acetic acid is 4.74 and that of chloroacetic acid and trichloroacetic acid is 2.86 and 0.66 respectively.

Now, comparing the O-H bond polarity of all the three acids, since, chlorine is electronegative in nature, if it is attached to the carbonyl carbon, the polarity of O-H bond increases, the O-H bond become weak making the compound more acidic.

Due to the presence of 3 chlorine atoms, trichloroacetic acid is more acidic than the chloroacetic acid which is then more acidic than acetic acid.

The pKa of an acid is defined as negative log of the acid dissociation constant.

It is mathematically represented as follows:

  pKa=logKa

Here, Ka is acid dissociation constant of an acid.

Taking example of dissociation of acetic acid, the reaction will be as follows:

  CH3COOHCH3COO+H+

The expression for acid dissociation constant can be written as follows:

  Ka=[CH3COO][H+][CH3COOH]

More the value of pKa , less will be the acidity. Thus, trichloroacetic acid will be more acetic.

The solution of the known concentration of the acetic acid, chloroacetic acid and trichloroacetic acid in different flask and the pH of the solution is determined by using pH meter.

The concentration of the proton ion is calculated by the formula:

  [H+]=antilog(pH)

The concentration of the proton is same as that of the conjugate base of the acids. Also the concentrations of the acids are known.

Thus, the equilibrium concentration of the acid is calculated by the formula:

  Ka=Concentrationofconjugatebase×ConcentrationoftheprotonConcentrationoftheacid

Hence, using the Ka values, the pKa of the acids are calculated as:

  pKa=logKa

Conclusion

The pKa of the acids are calculated as:

  pKa=logKa

(b)

Interpretation Introduction

To determine: An experiment to determine the solubility of acetic acid, chloroacetic acid and trichloroacetic acid.

(b)

Expert Solution
Check Mark

Answer to Problem 1DE

Solution: As the value of pKa increases, the acidity of the acids and the solubility of the salt formed from these acids decreases.

Explanation of Solution

The solubility of any salt depends on its concentration, which is related to pH and pKa of acid as follows:

  pH=pka+log[salt][acid]

The above equation is Henderson-Hasselbach equation.

From the above equation, if the pH of solution decreases, the acid concentration increases and that of salt decreases.

Since, the acidity of acetic acid is least thus, its solution has maximum pH value and its sodium salt has maximum solubility.

The trichloroacetic acid is strongest acid and has minimum pH thus, its sodium salt has minimum solubility.

Conclusion

As the value of pKa increases, the acidity of the acids and the solubility of the salt formed from these acids decreases.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Chapter 17 Solutions

Chemistry the Central Science 13th Edition Custom for Lamar University

Ch. 17.2 - Prob. 17.6.1PECh. 17.2 - Prob. 17.6.2PECh. 17.3 - Prob. 17.7.1PECh. 17.3 - 8.103 The compound chloral hydrate, known in...Ch. 17.3 - Barium azide is 62.04% Ba and 37.96% N. Each azide...Ch. 17.3 - Acetylene (C2H2) and nitrogen (N2) both contain a...Ch. 17.3 - Prob. 17.9.1PECh. 17.3 - Prob. 17.9.2PECh. 17.4 - Prob. 17.10.1PECh. 17.4 - Prob. 17.10.2PECh. 17.4 - Prob. 17.11.1PECh. 17.4 - A new compound is made that has a C-C bond length...Ch. 17.4 - A new compound is made that has an N-N bond length...Ch. 17.4 - Prob. 17.12.2PECh. 17.5 - Prob. 17.13.1PECh. 17.5 - An ionic substance of formula MX has a lattice...Ch. 17.5 - Prob. 17.14.1PECh. 17.5 - Prob. 17.14.2PECh. 17.5 - Prob. 17.15.1PECh. 17.5 - Consider the collection of nonmetallic elements 0,...Ch. 17.6 - The substance chlorine monoxide, CIO(g), is...Ch. 17.6 - [8.87] a. using the electronegativities of Br...Ch. 17.6 - Prob. 17.17.1PECh. 17.6 - Although I3- is a known ion, F3- is not. a. Draw...Ch. 17 - Prob. 1DECh. 17 - 9.13 a. An AB2 molecule is linear. How...Ch. 17 - Give the electron-domain and molecular geometries...Ch. 17 - Prob. 3ECh. 17 - Prob. 4ECh. 17 - Prob. 5ECh. 17 - Prob. 6ECh. 17 - Prob. 7ECh. 17 - Prob. 8ECh. 17 - Azo dyes are organic dyes that are used for many...Ch. 17 - Prob. 10ECh. 17 - 9.1 A certain AB4, molecule has a "seesaw" shape...Ch. 17 - Prob. 12ECh. 17 - Prob. 13ECh. 17 - Prob. 14ECh. 17 - Prob. 15ECh. 17 - In the hydrocarbon a. What is the hybridization at...Ch. 17 - The drawing below shows the overlap of two hybrid...Ch. 17 - Prob. 18ECh. 17 - 9.10 The following is part of a molecular...Ch. 17 - a. Methane (CH4) and the perchlorate ion (C104-)...Ch. 17 - Prob. 21ECh. 17 - Prob. 22ECh. 17 - Prob. 23ECh. 17 - Prob. 24ECh. 17 - In which of these molecules or ions does the...Ch. 17 - Prob. 26ECh. 17 - How many nonbonding electron pairs are there in...Ch. 17 - Prob. 28ECh. 17 - Prob. 29ECh. 17 - Prob. 30ECh. 17 - Prob. 31ECh. 17 - Prob. 32ECh. 17 - Prob. 33ECh. 17 - Prob. 34ECh. 17 - Ammonia, NH3 reacts with incredibly strong bases...Ch. 17 - In which of the following AFn molecules or ions is...Ch. 17 - a. Explain why BrF4 is square planar, whereas...Ch. 17 - 9.34 Name the proper three-dimensional molecule...Ch. 17 - Prob. 39ECh. 17 - Prob. 40ECh. 17 - a. (a) Is the molecule BF3 polar or nonpolar? b....Ch. 17 - Prob. 42ECh. 17 - Predict whether each of the following molecules is...Ch. 17 - Prob. 44ECh. 17 - Prob. 45ECh. 17 - Prob. 46ECh. 17 - For each statement, irldicate whether it is true...Ch. 17 - Draw sketches illustrating the overlap between the...Ch. 17 - For each statement, indicate whether it is true or...Ch. 17 - Consider the SC12 molecule. a. What IS the...Ch. 17 - Prob. 51ECh. 17 - Prob. 52ECh. 17 - Prob. 53ECh. 17 - Prob. 54ECh. 17 - Prob. 55ECh. 17 - Prob. 56ECh. 17 - a. Draw Lewis structures for ethane (C2He),...Ch. 17 - a. Draw Lewis structures for ethane (C2He),...Ch. 17 - Prob. 59ECh. 17 - Prob. 60ECh. 17 - Prob. 61ECh. 17 - Prob. 62ECh. 17 - In the formate ion, HC02- , the carbon atom is the...Ch. 17 - Prob. 64ECh. 17 - Prob. 65ECh. 17 - Prob. 66ECh. 17 - Prob. 67ECh. 17 - a. If you combine two atomic orbitals on two...Ch. 17 - Prob. 69ECh. 17 - Indicate whether each statement is true or false....Ch. 17 - Prob. 71ECh. 17 - Prob. 72ECh. 17 - Prob. 73ECh. 17 - Prob. 74ECh. 17 - Prob. 75ECh. 17 - Prob. 76ECh. 17 - Determine the electron configurations for CN+, CN,...Ch. 17 - Prob. 78ECh. 17 - Consider the molecular orbitals of the P2...Ch. 17 - Prob. 80ECh. 17 - Consider the following XF4 ions: PF4, BrF4-,...Ch. 17 - 9.88 Consider the molecule PF4Cl....Ch. 17 - Prob. 83AECh. 17 - Fill in the blank spaces in the following chart....Ch. 17 - Prob. 85AECh. 17 - Prob. 86AECh. 17 - Prob. 87AECh. 17 - Prob. 88AECh. 17 - Prob. 89AECh. 17 - Prob. 90AECh. 17 - Prob. 91AECh. 17 - Prob. 92AECh. 17 - In ozone, 03, the two oxygen atoms on the ends Of...Ch. 17 - Butadiene, C4H6, is a planar molecule that has the...Ch. 17 - The structure of borazine, B3N3H6, is a...Ch. 17 - Prob. 96AECh. 17 - Prob. 97AECh. 17 - Prob. 98AECh. 17 - Prob. 99AECh. 17 - Prob. 100AECh. 17 - Prob. 101AECh. 17 - Consider the following AB3 molecules and ions-...Ch. 17 - Prob. 103AECh. 17 - Prob. 104AECh. 17 - Prob. 105AECh. 17 - Prob. 106AECh. 17 - Prob. 107AECh. 17 - Prob. 108AECh. 17 - Determine whether the following molecules are...Ch. 17 - Prob. 110IECh. 17 - Prob. 111IECh. 17 - Prob. 112IECh. 17 - Prob. 113IECh. 17 - Prob. 114IECh. 17 - Prob. 115IECh. 17 - Prob. 116IECh. 17 - Prob. 117IECh. 17 - Prob. 118IECh. 17 - Prob. 119IECh. 17 - Prob. 120IE
Knowledge Booster
Background pattern image
Chemistry
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Text book image
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Text book image
Chemistry
Chemistry
ISBN:9781259911156
Author:Raymond Chang Dr., Jason Overby Professor
Publisher:McGraw-Hill Education
Text book image
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning
Text book image
Organic Chemistry
Chemistry
ISBN:9780078021558
Author:Janice Gorzynski Smith Dr.
Publisher:McGraw-Hill Education
Text book image
Chemistry: Principles and Reactions
Chemistry
ISBN:9781305079373
Author:William L. Masterton, Cecile N. Hurley
Publisher:Cengage Learning
Text book image
Elementary Principles of Chemical Processes, Bind...
Chemistry
ISBN:9781118431221
Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:WILEY