Ch. 17 Applications of Aqueous Equilibria: Buffers and Titrations
|
|
- Peter Watkins
- 6 years ago
- Views:
Transcription
1 Ch. 17 Applications of Aqueous Equilibria: Buffers and Titrations Sec 1 The Common-Ion Effect: The dissociation of a weak electrolyte decreases when a strong electrolyte that has an ion in common with the weak electrolyte is added to the solution. A. Examples include: 1) a solution containing a WA + soluble salt of the WA 2) a solution containing a WB + a soluble salt of the WB Suppose we have a weak acid and a soluble salt of that acid. CH 3 COOH NaCH 3 COO CH 3 COOH CH 3 COO + H + Since NaCH 3 COO provides a high concentration of acetate ions (common ions), adding it to the solution By Le Chatelier The result is that (shifts the equilibrium far to the left) (H+ concentration is drastically decreased) B. How does this equilibrium reaction act as a buffer system? + NH 3 + H 2 O <---> NH 4 + OHanswer: If an acid is added NH 3 will accept a proton, formed NH + 4. As ammonia increases, the equilibrium shifts to the left, forming more ammonia. If a base is added, the increase in hydroxide shifts the reaction to the left. Ex. #1: Find the ph of a solution containing M HNO 2 (K a = 4.5 x 10 4 ) and 0.10 M KNO 2. Sec 2. Buffered Solutions ( buffers ) A. contain a weak conjugate acid-base pair B. contain an acidic species and a basic species that do NOT consume each other through neutralization C. Buffer solutions resist changes in ph because they react with both hydronium and hydroxide ions. Ex #2: For a CH 3 COOH and-ch 3 COO buffer, you could use 1
2 For an NH 4 + -and-nh 3 buffer, you could use D. When an acid is added to a salt solution... What happens when an acid is added to a salt solution instead of just pure water. How does the presence of a salt affect the dissociation of the acid? Problem: A. Calculate the ph of a solution that is 0.10 M acetic acid AND 0.10 M sodium acetate. First, let's write the reaction for the dissociation of the salt, sodium acetate and identify the concentrations of each of the components: NOTE: The concentrations of the ions are the same as the concentration of the salt because the mole ratio is 1:1. Now, let's set up the REACTION for the dissociation of the acetic acid. Now, we set up our concentration CHART. Remember, however, that the initial concentrations for the conjugate base, C 2 H 3 O 2 - is no longer 0 because of the salt: [HC 2 H 3 O 2 [H 3 O + ] [C 2 H 3 O 2 - Initial: 0.10 M M Equilibrium: 0.10 M M + ASSUME is negligible when subtracted and added: 2
3 CHECK the assumption: Since the acid dissociates less than 5%, is negligible when added and subtracted M 1.8 x 10-5 M 0.10 M In a sample of this buffer, [CH 3 COOH] and ] [CH 3 COO-] are about 5000 x greater than [H 3 O + ]. If a small amount of hydronium is added, it will be quickly converted to acetic acid. If a small amount of hydroxide is added, it will neutralize hydronium, but CH 3 COOH will dissociate and maintain the ph fairly constant. B. Considering the same system in A, suppose mol of NaOH is added to this buffer solution. What will the ph of the resulting solution be? Step 1: Stoich part HC 2 H 3 O 2 + H 2 O H 3 O+ + C 2 H 3 O 2 - buffer 0.10 M 1.7 x M after M? 0.11 M NaOH addition Step 2: Equilibrium part [H 3 O+] (.11) = 1.7 x 10-5 (0.090) [H 3 O+] = 1.7 x 10-5 (.090) = 1.4 x 10-5 ph = -log 1.4 x 10-5 = 4.85 (.11) 1. Addition of.010 mol of NaOH changes the ph by only 0.15 units. (refer to ph= 4.7 in Part A) 2. A similar addition of pure water changes the ph by 5 units (from 7 to 12). 3
4 Ex. #3: Find the ph of a buffer that is 0.12 M lactic acid, HC 3 H 5 O 3 (K a = 1.4 x 10 4 ) and 0.10 M sodium lactate. (answer: 3.8) Sec 2. Addition of Strong Bases to Buffer -- Reactions between strong acids/bases and weak bases/acids proceed to completion. -- We assume the strong acid/base is completely consumed. Sec 3 Buffer Capacity: the amount of acid or base the buffer can neutralize before the ph begins to change appreciably. 2 calculations needed: 1) the ph of a solution where the buffer capacity has been exceeded; 2) choose among alternatives the best buffer system for a given ph. Problem 1: Calculate the ph of the M HCOOH/0.100 HCOONa a buffer used after the addition of 10.0 ml of 6.00 M NaOH to the original buffered solution volume of ml. Strategy: 1) determine the moles of weak acid and base existing after the addition of the SB (stoich part); 2) calculate the ph of the buffered solution after you have your new equilibrium conc. (equilibrium part) 1) stoichiometry part mmoles HCOOH initial = mmol/ml x ml = 125 mmol mmoles HCOO - initial = mmol/ml x ml = 50.0 mmol mmol OH-added = 6.00 mmol/ml x 10.0 ml = 60.0 mmol HCOOH + OH- ----> HCOO- I (mmol) F (mmol) after addition of NaOH, [HCOOH] = 65.0 mmol/510 ml = M (500+10) equilibrium concentration [HCOO-] = 110 mmol/510 ml = M 2) equilibrium part The acid dissociation of HCOOH is the significant factor here. 4
5 Ka = [H+][HCOO-] [HCOOH] 1.8 x 10-4 = [H+][0.216] => [H+] = 1.1 x 10-4 ph = 4.0 (5% rule holds) [0.128] Ex.#4: A buffered solution of ph 4.74 contains 0.30 mol CH 3 COOH (K a = 1.8 x 10 5 ) and 0.30 mol NaCH 3 COO. Calculate the ph after mol NaOH is added. Ignore volume changes. Alternately, you could use the Henderson-Hasselbalch equation: ph pka log A HA poh pkb log HB B where pka = -log Ka where pk b = -log K b Problem 2: Calculate the poh and ph of a solution that is 0.20 M in NH 3 and 0.10 M in NH 4 Cl. NH H 2 O <----> NH 4 + OH-.20 M 0.10 M -x +x +x.20-x 0.10+x x K b = 1.7 x 10-5 (given) pk b = -log 1.7 x 10-5 pk b = 4.77 (Use H-H formula): poh = pk b + log (salt) where pk b = -log K b base poh = log (.10)/(.20) = = 4.47 ph = = 9.53 Problem 3: What is the ph a solution containing 2.00 mol of ammonia and 3.00 mol of ammonium chloride in a volume of 1.00 L? K b = 1.81 x ways to solve the problem 5
6 Way 1: Do ICE and the K b expression: NH H 2 O <----> NH 4 + OH- K b = [ NH +1 4 ][ OH-] = ( x) (x) = 1.81 x 10-5 [NH 3 ] (2.00-x) assume x small: 1.81 x 10-5 = 3.00 x 2.00 x = 1.21 x 10-5 poh = ph = Way 2: Henderson/Hasselbach equation: (for acids) ph = pka + log [A-] HA] OR (for bases) poh = pkb +log [HB + ] [B] = log = ph = Sec4 Acid-Base Titrations & Indicators A. Most acid-base indicators are weak organic acids (HIn) or weak organic bases (InOH). In represents complex organic groups. B. Bromothymol blue is an acid-base indicator that is a weak acid and has a Ka of about 1 x HIn + H 2 O <---> H 3 O+ + In- (yellow) (blue) Ka = [H 3 O+] [ In-] = 1 x 10-7 [HIn] Problem: The yellow color of the bromothymol blue indicator can be seen when the acid form (Hin) is 6.3 x more concentrated that the ionized form (In-). The blue color can be seen when In- is 4 x more concentrated than Hin. What is the ph range over which this color change occurs? Yellow color H 3 O+ = Ka [HIn] = 1 x 10-7 (6.3) [In] H 3 O+ = 6.3 x 10-7 ph = -log 6.3 x 10-7 = 6.2 blue color H 3 O+ = Ka [HIn] = 1 x 10-7 [In-] 4.0 H 3 O+ = 2.5 x 10-8 M ph = 7.6 6
7 1. Yellow color is seen at a ph at 6.2 or below. This blue color is seen at a ph of 7.6 or above. 2. The pt at which the color change for the indicator occurs in a titration is the endpt. 3. The equivalence pt of a titration is the pt at which chemically equivalent amounts of A and B have reacted. 4. Ideally, the endpt and the equivalence pt should coincide in a titration. Sec 5 Strong Acid Strong Base Titrations H+ + OH > H 2 O The reverse reaction of the autoionization ph curve for HCl titrated with NaOH of water is K = 1/K w K = 1/ 1 x This reaction is certainly complete; This type of titration is less an equilibrium problem than a stoich one. ph 7 *Any indicator whose color change begins and ends along the vertical line is okay. -- phenolphthalein (ph ) base = acid = -- methyl red (ph ) base = acid = ml of NaOH added Problem 1: What is the ph of a solution containing ml of a M HCl to which ml of a M solution of NaOH has been titrated? Step 1: calculate the # of moles HCl and NaOH initially present 0.100mol/L x L = moles HCl *MV = moles mol/l x L = moles NaOH HCl + NaOH ----> NaCl + H 2 O start.00250mol mol 0 mol change mol mol mol after rxn mol 0 mol mol Step 2: Calculate the M of acid (or base) both are STRONG! HCl = mol =.0430 M L (total volume) 7
8 [H 3 O+] = 4.30 x 10-2 M ph = -log 4.30 x 10-2 M = *After ml of M NaOH has been titrated (the equivalence pt), the ph is 7.00 because the NaOH exactly neutralizes the HCl. Ex # 5: Calculate the ph after the 4.00 ml of M HCl have been added to ml of M NaOH. (ans: ph =13.1) Ex. #6: Find ph when ml of 0.10 M HNO 3 are mixed with ml of 0.10 M KOH. (ph = 10.3) Weak Acid Strong Base Titrations The equivalence point is when, say, 50.0 ml of 0.10 M NaOH have been added to 50.0 ml of 0.10 M CH 3 COOH, but ph is > 7 at that point because... p H 7 ph curve for CH 3 COOH titrated with NaOH ml of NaOH added EX #7: (in 5 steps) A ml of M nitrous acid (pka = 3.35) was titrated with M NaOH. Calculate the ph of the solution after the following quantities of base have been added to the acid solution: A) 0.00 ml B) 25.00mL, C) ml, D) ml ph curve for H 2 CO 3 Titration curves for polyprotic acids (H 2 CO 3 ) look something like -- they have... ph 8
Aqueous Equilibria, Part 2 AP Chemistry Lecture Outline
Aqueous Equilibria, Part 2 AP Chemistry Lecture Outline Name: The Common-Ion Effect Suppose we have a weak acid and a soluble salt of that acid. CH 3 COOH NaCH 3 COO CH 3 COOH CH 3 COO + H + Since NaCH
More informationAcid-Base Solutions - Applications
Acid-Base Solutions - Applications 1 The Common Ion Effect Consider the equilibrium established when acetic acid, HC 2 H 3 O 2, is added to water. CH 3 COOH(aq) + H 2 O(l) CH 3 COO - (aq) + H 3 O + (aq)
More informationChapter 15. Acid-Base Equilibria
Chapter 15 Acid-Base Equilibria The Common Ion Effect The common-ion effect is the shift in an ionic equilibrium caused by the addition of a solute that provides an ion already involved in the equilibrium
More informationChapter 17 Additional Aspects of Aqueous Equilibria (Part A)
Chapter 17 Additional Aspects of Aqueous Equilibria (Part A) Often, there are many equilibria going on in an aqueous solution. So, we must determine the dominant equilibrium (i.e. the equilibrium reaction
More informationHALFWAY to EQUIVALENCE POINT: ph = pk a of the acid being titrated.
CHEMISTRY 109 Help Sheet #33 Titrations Chapter 15 (Part II); Section 15.2 ** Cover topics appropriate for your lecture** Prepared by Dr. Tony Jacob http://www.chem.wisc.edu/areas/clc (Resource page) Nuggets:
More informationChem Chapter 18: Sect 1-3 Common Ion Effect; Buffers ; Acid-Base Titrations Sect 4-5 Ionic solubility Sect 6-7 Complex Formation
Chem 106 3--011 Chapter 18: Sect 1-3 Common Ion Effect; Buffers ; Acid-Base Titrations Sect 4-5 Ionic solubility Sect 6-7 Complex Formation 3//011 1 The net ionic equation for the reaction of KOH(aq) and
More informationChapter 17 Additional Aspects of Aqueous Equilibria (Part A)
Chapter 17 Additional Aspects of Aqueous Equilibria (Part A) What is a dominant equilibrium? How do we define major species? Reactions between acids and bases 1. Strong Acids + Strong Base The reaction
More informationApplications of Aqueous Equilibria Chapter 15. Titration Curves & Indicators Sections 4-5
Applications of Aqueous Equilibria Chapter 15 Titration Curves & Indicators Sections 45 Strong Acid vs. Strong Base Titration Titrate 50.0 ml of 0.200 M HNO 3 with 0.100 M NaOH What is the ph when no NaOH
More informationSchool of Chemistry, University of KwaZulu-Natal, Howard College Campus, Durban. CHEM191 Tutorial 1: Buffers
School of Chemistry, University of KwaZulu-Natal, Howard College Campus, Durban CHEM191 Tutorial 1: Buffers Preparing a Buffer 1. How many moles of NH 4 Cl must be added to 1.0 L of 0.05 M NH 3 to form
More informationThe Common Ion Effect
Chapter 17 ACID BASE EQUILIBRIA (Part I) Dr. Al Saadi 1 17.1 The Common Ion Effect A phenomenon known as the common ion effect states that: When a compound containing an ion in common with an already dissolved
More informationLecture 12. Acid/base reactions. Equilibria in aqueous solutions.
Lecture 12 Acid/base reactions. Equilibria in aqueous solutions. Titrations Kotz 7 th ed. Section 18.3, pp.821-832. In a titration a solution of accurately known concentration is added gradually added
More informationBuffer solutions Strong acids and bases dissociate completely and change the ph of a solution drastically. Buffers are solutions that resist changes i
18.3 ph Curves Buffer solutions Strong acids and bases dissociate completely and change the ph of a solution drastically. Buffers are solutions that resist changes in ph even when acids and bases are added
More informationE. Incorrect. Look carefully there is a statement that is true about weak acid dissociation.
AP Chemistry - Problem Drill 21: Acids and Bases No. 1 of 10 1. Which of the following is true for the dissociation of a weak acid? A. K a is large. B. The equilibrium lies far to the right. C. The equilibrium
More informationChapter 17. Additional Aspects of Aqueous Equilibria. Lecture Presentation. James F. Kirby Quinnipiac University Hamden, CT
Lecture Presentation Chapter 17 Additional Aspects of James F. Kirby Quinnipiac University Hamden, CT Effect of Acetate on the Acetic Acid Equilibrium Acetic acid is a weak acid: CH 3 COOH(aq) H + (aq)
More informationADVANCED PLACEMENT CHEMISTRY ACIDS, BASES, AND AQUEOUS EQUILIBRIA
ADVANCED PLACEMENT CHEMISTRY ACIDS, BASES, AND AQUEOUS EQUILIBRIA Acids- taste sour Bases(alkali)- taste bitter and feel slippery Arrhenius concept- acids produce hydrogen ions in aqueous solution while
More informationLecture #11-Buffers and Titrations The Common Ion Effect
Lecture #11-Buffers and Titrations The Common Ion Effect The Common Ion Effect Shift in position of an equilibrium caused by the addition of an ion taking part in the reaction HA(aq) + H2O(l) A - (aq)
More informationKotz 7 th ed. Section 18.3, pp
Lecture 15 Acid/base reactions. Equilibria in aqueous solutions. Titrations Kotz 7 th ed. Section 18.3, pp.821-832. In a titration a solution of accurately known concentration is added gradually added
More informationTry this one Calculate the ph of a solution containing M nitrous acid (Ka = 4.5 E -4) and 0.10 M potassium nitrite.
Chapter 17 Applying equilibrium 17.1 The Common Ion Effect When the salt with the anion of a is added to that acid, it reverses the dissociation of the acid. Lowers the of the acid. The same principle
More informationAcid-Base Equilibria (Chapter 10.) Problems: 2,3,6,13,16,18,21,30,31,33
Acid-Base Equilibria (Chapter 10.) Problems: 2,3,6,13,16,18,21,30,31,33 Review acid-base theory and titrations. For all titrations, at the equivalence point, the two reactants have completely reacted with
More informationAcid Base Equilibria
Acid Base Equilibria Acid Ionization, also known as acid dissociation, is the process in where an acid reacts with water to produce a hydrogen ion and the conjugate base ion. HC 2 H 3 O 2(aq) H + (aq)
More informationChapter 17. Additional Aspects of Aqueous Equilibria. Lecture Presentation. John D. Bookstaver St. Charles Community College Cottleville, MO
Lecture Presentation Chapter 17 Additional Aspects of John D. Bookstaver St. Charles Community College Cottleville, MO The Common-Ion Effect Consider a solution of acetic acid: CH 3 COOH(aq) + H 2 O(l)
More informationAP Chapter 15 & 16: Acid-Base Equilibria Name
AP Chapter 15 & 16: Acid-Base Equilibria Name Warm-Ups (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8. AP Chapter 15 & 16: Acid-Base Equilibria 2 Warm-Ups (Show
More informationAcid-Base Equilibria. 1.NH 4 Cl 2.NaCl 3.KC 2 H 3 O 2 4.NaNO 2. Acid-Ionization Equilibria. Acid-Ionization Equilibria
Acid-Ionization Equilibria Acid-Base Equilibria Acid ionization (or acid dissociation) is the reaction of an acid with water to produce hydronium ion (hydrogen ion) and the conjugate base anion. (See Animation:
More informationApplications of Aqueous Equilibria. Chapter 18
Applications of Aqueous Equilibria Chapter 18 What we learn from Chap 18 This chapter is the third in the three-chapter sequence about equilibrium, this one building upon the core principles raised in
More informationTitration a solution of known concentration, called a standard solution
Acid-Base Titrations Titration is a form of analysis in which we measure the volume of material of known concentration sufficient to react with the substance being analyzed. Titration a solution of known
More informationAP CHEMISTRY NOTES 10-1 AQUEOUS EQUILIBRIA: BUFFER SYSTEMS
AP CHEMISTRY NOTES 10-1 AQUEOUS EQUILIBRIA: BUFFER SYSTEMS THE COMMON ION EFFECT The common ion effect occurs when the addition of an ion already present in the system causes the equilibrium to shift away
More informationChapter 17: Additional Aspects of Aqueous equilibria. Common-ion effect
Chapter 17: Additional Aspects of Aqueous equilibria Learning goals and key skills: Describe the common ion effect. Explain how a buffer functions. Calculate the ph of a buffer solution. Calculate the
More informationAP Study Questions
Name: Class: Date: AP 17.1-17.2 Study Questions True/False Indicate whether the statement is true or false. 1. The extent of ionization of a weak electrolyte is increased by adding to the solution a strong
More information16.3 Weak Acids Weak Bases Titration
16.3 Weak Acids Weak Bases Titration Titration of Weak Acid with Strong Base Titration of Base Acid with Strong Acid Dr. Fred Omega Garces Chemistry 201 Miramar College 1 Weak Acids Weak Bases Titration
More informationPart One: Pure Solutions of Weak Acids, Bases (water plus a single electrolyte solute)
CHAPTER 16: ACID-BASE EQUILIBRIA Part One: Pure Solutions of Weak Acids, Bases (water plus a single electrolyte solute) A. Weak Monoprotic Acids. (Section 16.1) 1. Solution of Acetic Acid: 2. See Table
More informationFind this material useful? You can help our team to keep this site up and bring you even more content consider donating via the link on our site.
Find this material useful? You can help our team to keep this site up and bring you even more content consider donating via the link on our site. Still having trouble understanding the material? Check
More informationACID-BASE EQUILIBRIA. Chapter 14 Big Idea Six
ACID-BASE EQUILIBRIA Chapter 14 Big Idea Six Acid-Base Equilibria Common Ion Effect in Acids and Bases Buffer SoluDons for Controlling ph Buffer Capacity ph-titradon Curves Acid-Base TitraDon Indicators
More informationEquilibri acido-base ed equilibri di solubilità. Capitolo 16
Equilibri acido-base ed equilibri di solubilità Capitolo 16 The common ion effect is the shift in equilibrium caused by the addition of a compound having an ion in common with the dissolved substance.
More informationChemical Equilibrium
Chemical Equilibrium Many reactions are reversible, i.e. they can occur in either direction. A + B AB or AB A + B The point reached in a reversible reaction where the rate of the forward reaction (product
More informationAcid-Base Equilibria. 1.NH 4 Cl 2.NaCl 3.KC 2 H 3 O 2 4.NaNO 2. Solutions of a Weak Acid or Base
Acid-Base Equilibria 1 Will the following salts be acidic, basic or neutral in aqueous solution? 1.NH 4 Cl.NaCl.KC H O 4.NaNO A = acidic B = basic C = neutral Solutions of a Weak Acid or Base The simplest
More informationACID-BASE REACTIONS. Titrations Acid-Base Titrations
Page III-b-1 / Chapter Fourteen Part II Lecture Notes ACID-BASE REACTIONS Chapter (Part II A Weak Acid + Strong Base Titration Titrations In this technique a known concentration of base (or acid is slowly
More informationChemistry, The Central Science, 11th edition Theodore L. Brown; H. Eugene LeMay, Jr.; Bruce E. Bursten; Catherine J. Murphy.
Chemistry, The Central Science, 11th edition Theodore L. Brown; H. Eugene LeMay, Jr.; Bruce E. Bursten; Catherine J. Murphy Chapter 17 Additional Aspects of Aqueous Equilibria Ahmad Aqel Ifseisi Assistant
More informationDr. Diala Abu-Hassan, DDS, PhD Lecture 3 MD summer 2014
ph, DDS, PhD Dr.abuhassand@gmail.com Lecture 3 MD summer 2014 www.chem4kids.com 1 Outline ph Henderson-Hasselbalch Equation Monoprotic and polyprotic acids Titration 2 Measuring the acidity of solutions,
More informationChapter 17 Additional Aspects of
Chemistry, The Central Science, 11th edition Theodore L. Brown; H. Eugene LeMay, Jr.; and Bruce E. Bursten Chapter 17 Additional Aspects of AP Chemistry 2014-15 North Nova Education Centre Mr. Gauthier
More informationCh. 14/15: Acid-Base Equilibria Sections 14.6, 14.7, 15.1, 15.2
Ch. 14/15: Acid-Base Equilibria Sections 14.6, 14.7, 15.1, 15.2 Creative Commons License Images and tables in this file have been used from the following sources: OpenStax: Creative Commons Attribution
More informationAnalytical Chemistry Lecture III by/ Dr. Ekhlas Q. J. BUFFER SOLUTIONS
Analytical Chemistry Lecture III by/ Dr. Ekhlas Q. J. BUFFER SOLUTIONS Buffer solutions Definition Solutions which resist changes in ph when small quantities of acid or alkali are added. a solution that
More informationChapter 17 Additional Aspects of
Chemistry, The Central Science, 11th edition Theodore L. Brown; H. Eugene LeMay, Jr.; and Bruce E. Bursten Chapter 17 Additional Aspects of John D. Bookstaver St. Charles Community College Cottleville,
More information1.12 Acid Base Equilibria
.2 Acid Base Equilibria BronstedLowry Definition of acid Base behaviour A BronstedLowry acid is defined as a substance that can donate a proton. A BronstedLowry base is defined as a substance that can
More informationChapter 14 Acid- Base Equilibria Study Guide
Chapter 14 Acid- Base Equilibria Study Guide This chapter will illustrate the chemistry of acid- base reactions and equilibria, and provide you with tools for quantifying the concentrations of acids and
More informationChap 17 Additional Aspects of Aqueous Equilibria. Hsu Fu Yin
Chap 17 Additional Aspects of Aqueous Equilibria Hsu Fu Yin 1 17.1 The Common-Ion Effect Acetic acid is a weak acid: CH 3 COOH(aq) H + (aq) + CH 3 COO (aq) Sodium acetate is a strong electrolyte: NaCH
More informationCHAPTER 7.0: IONIC EQUILIBRIA
Acids and Bases 1 CHAPTER 7.0: IONIC EQUILIBRIA 7.1: Acids and bases Learning outcomes: At the end of this lesson, students should be able to: Define acid and base according to Arrhenius, Bronsted- Lowry
More informationAdvanced Placement Chemistry Chapters Syllabus
As you work through the chapter, you should be able to: Advanced Placement Chemistry Chapters 14 16 Syllabus Chapter 14 Acids and Bases 1. Describe acid and bases using the Bronsted-Lowry, Arrhenius, and
More informationAcid-Base Equilibria and Solubility Equilibria Chapter 17
PowerPoint Lecture Presentation by J. David Robertson University of Missouri Acid-Base Equilibria and Solubility Equilibria Chapter 17 The common ion effect is the shift in equilibrium caused by the addition
More informationChapter 8: Applications of Aqueous Equilibria
Chapter 8: Applications of Aqueous Equilibria 8.1 Solutions of Acids or Bases Containing a Common Ion 8.2 Buffered Solutions 8.3 Exact Treatment of Buffered Solutions 8.4 Buffer Capacity 8.5 Titrations
More informationKEY. Practice Problems: Applications of Aqueous Equilibria
Practice Problems: Applications of Aqueous Equilibria KEY CHEM 1B 1. Ammonia (NH3) is a weak base with a Kb = 1.8 x 1 5. a) Write the balanced chemical equation for the reaction of ammonia with water.
More information12. Acid Base Equilibria
2. Acid Base Equilibria BronstedLowry Definition of acid Base behaviour A BronstedLowry acid is defined as a substance that can donate a proton. A BronstedLowry base is defined as a substance that can
More informationGrace King High School Chemistry Test Review
CHAPTER 19 Acids, Bases & Salts 1. ACIDS Grace King High School Chemistry Test Review UNITS 7 SOLUTIONS &ACIDS & BASES Arrhenius definition of Acid: Contain Hydrogen and produce Hydrogen ion (aka proton),
More informationChemical Equilibrium. Many reactions are, i.e. they can occur in either direction. A + B AB or AB A + B
Chemical Equilibrium Many reactions are, i.e. they can occur in either direction. A + B AB or AB A + B The point reached in a reversible reaction where the rate of the forward reaction (product formation,
More information4. Acid Base Equilibria
4. Acid Base Equilibria BronstedLowry Definition of acid Base behaviour A BronstedLowry acid is defined as a substance that can donate a proton. A BronstedLowry base is defined as a substance that can
More informationAcid-Base Equilibria and Solubility Equilibria
ACIDS-BASES COMMON ION EFFECT SOLUBILITY OF SALTS Acid-Base Equilibria and Solubility Equilibria Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 2 The common
More informationQuestions #4-5 The following two questions refer to the following system: A 1.0L solution contains 0.25M HF and 0.60M NaF (Ka for HF = 7.2 x 10-4 ).
Multiple Choice 1) A solution contains 0.250 M HA (K a = 1.0 x 10-6 ) and 0.45 M NaA. What is the ph after 0.10 mole of HCl is added to 1.00L of this solution? a. 3.17 b. 3.23 c. 6.00 d. 10.77 e. 10.83
More informationChemistry 192 Problem Set 4 Spring, 2018 Solutions
Chemistry 192 Problem Set 4 Spring, 2018 Solutions 1. The ionization constant of benzoic acid in water associated with the reaction C 6 H 5 COOH (aq) + H 2 O (l) C 6 H 5 COO (aq) + H 3O + (aq) is K a =
More informationAdditional Aspects of Aqueous Equilibria David A. Katz Department of Chemistry Pima Community College
Additional Aspects of Aqueous Equilibria David A. Katz Department of Chemistry Pima Community College The Common Ion Effect Consider a solution of acetic acid: HC 2 H 3 O 2(aq) + H 2 O (l) H 3 O + (aq)
More informationWhat we learn from Chap 18
Applications of Aqueous Equilibria Chapter 18 What we learn from Chap 18 18.2 This chapter is the third in the three-chapter sequence about equilibrium, this one building upon the core principles raised
More informationChapter 17. Additional Aspects of Aqueous Equilibria 蘇正寬 Pearson Education, Inc.
Chapter 17 Additional Aspects of Aqueous Equilibria 蘇正寬 chengkuan@mail.ntou.edu.tw Additional Aspects of Aqueous Equilibria 17.1 The Common-Ion Effect 17.2 Buffers 17.3 Acid Base Titrations 17.4 Solubility
More informationChapter 10. Acids and Bases
Chapter 10 Acids and Bases 1 Properties of Aqueous Solutions of Acids and Bases Aqueous acidic solutions have the following properties: 1. They have a sour taste.. They change the colors of many indicators.
More informationFind this material useful? You can help our team to keep this site up and bring you even more content consider donating via the link on our site.
Find this material useful? You can help our team to keep this site up and bring you even more content consider donating via the link on our site. Still having trouble understanding the material? Check
More information1. Know and be capable of applying the Bronsted-Lowery model of acids and bases (inculdig the concepts related to conjugate acid-base pairs.
Acid-Base Equilibria You have just completed a chapter on equilibrium. That chapter focused primarily on gas phase reactions (with a few exceptions). This section on Acid-Base equilibria (along with the
More informationAcids and bases, ph and buffers. Dr. Mamoun Ahram Lecture 2
Acids and bases, ph and buffers Dr. Mamoun Ahram Lecture 2 ACIDS AND BASES Acids versus bases Acid: a substance that produces H+ when dissolved in water (e.g., HCl, H2SO4) Base: a substance that produces
More informationACID-BASE TITRATION AND PH
ACID-BASE TITRATION AND PH Section 1 Aqueous Solutions and the Concept of ph Hydronium and Hydroxide Ions Acids and bases form hydroxide and hydronium ions These ions are not the only ones in an aqueous
More informationGrade A buffer: is a solution that resists changes in its ph upon small additions of acid or base.sq1
Chapter 15 Lesson Plan Grade 12 402. The presence of a common ion decreases the dissociation. BQ1 Calculate the ph of 0.10M CH 3 COOH. Ka = 1.8 10-5. [H + ] = = ( )( ) = 1.34 10-3 M ph = 2.87 Calculate
More informationAcid and Base Titrations - Equation Guide
Acid and Base Titrations - Equation Guide Strong Acid + Strong Base: Initial Region: ph = - log (n sa / V sa ) or ph = - log (C sa ) Pre-Equivalence Region: ph = - log sa # or ph = - log Equivalence: ph
More informationConsider a normal weak acid equilibrium: Which direction will the reaction shift if more A is added? What happens to the % ionization of HA?
ch16blank Page 1 Chapter 16: Aqueous ionic equilibrium Topics in this chapter: 1. Buffers 2. Titrations and ph curves 3. Solubility equilibria Buffersresist changes to the ph of a solution. Consider a
More informationAcid-Base Equilibria. And the beat goes on Buffer solutions Titrations
Acid-Base Equilibria And the beat goes on Buffer solutions Titrations 1 Common Ion Effect The shift in equilibrium due to addition of a compound having an ion in common with the dissolved substance. 2
More information5.1.3 Acids, Bases and Buffers
5..3 Acids, Bases and Buffers BronstedLowry Definition of Acid Base behaviour A BronstedLowry acid is defined as a substance that can donate a proton. A BronstedLowry base is defined as a substance that
More informationConsider a 1.0 L solution of 0.10 M acetic acid. Acetic acid is a weak acid only a small percent of the weak acid is ionized
Chemistry 12 Acid- Base Equilibrium V Name: Date: Block: 1. Buffers 2. Hydrolysis Buffers An acid- base buffer is a solution that resists changes in ph following the addition of relatively small amounts
More informationChapter 17. Additional Aspects of Equilibrium
Chapter 17. Additional Aspects of Equilibrium 17.1 The Common Ion Effect The dissociation of a weak electrolyte is decreased by the addition of a strong electrolyte that has an ion in common with the weak
More informationApplications of Aqueous Equilibrium Chapter 15. Common Ion Effect & Buffers Sections 1-3
Applications of Aqueous Equilibrium Chapter 15 Common Ion Effect & Buffers Sections 1-3 Solutions of Acids or Bases Containing a Common Ion NaF Na + + F - HF H + + F - What effect does the NaF have on
More informationAcid Base Equilibrium Review
Acid Base Equilibrium Review Proof of true understanding of acid base equilibrium culminates in the ability to find ph of any solution or combination of solutions. The ability to determine ph of a multitude
More informationAcids And Bases. H + (aq) + Cl (aq) ARRHENIUS THEORY
Acids And Bases A. Characteristics of Acids and Bases 1. Acids and bases are both ionic compounds that are dissolved in water. Since acids and bases both form ionic solutions, their solutions conduct electricity
More informationChem 103 Exam #1. Identify the letter of the choice that best completes the statement or answers the question. Multiple Choice
Chem 103 Exam #1 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Which of the following can act as a Bronsted-Lowry base, but not as a Bronsted-Lowry
More informationThinking Like a Chemist About Acids and Bases. What are we going to learn today?
UNIT6-DAY6-LaB1230pm Page 1 UNIT6-DAY6-LaB1230pm Monday, February 25, 2013 2:48 PM Thinking Like a Chemist About Acids and Bases Part IV UNIT 6 DAY 6 What are we going to learn today? Apply the principles
More informationChapter 15. Acid-Base Equilibria
Chapter 15 Acid-Base Equilibria Section 15.1 Solutions of Acids or Bases Containing a Common Ion Common Ion Effect Shift in equilibrium position that occurs because of the addition of an ion already involved
More informationBuffer Effectiveness, Titrations & ph curves. Section
Buffer Effectiveness, Titrations & ph curves Section 16.3-16.4 Buffer effectiveness Buffer effectiveness refers to the ability of a buffer to resist ph change Effective buffers only neutralize small to
More informationUnderstanding the shapes of acid-base titration curves AP Chemistry
Understanding the shapes of acidbase titration curves AP Chemistry Neutralization Reactions go to Completion Every acidbase reaction produces another acid and another base. A neutralization reaction is
More informationCHAPTER 16 ACID-BASE EQUILIBRIA AND SOLUBILITY EQUILIBRIA
CHAPTER 16 ACID-BASE EQUILIBRIA AND SOLUBILITY EQUILIBRIA 16.3 (a) This is a weak acid problem. Setting up the standard equilibrium table: CH 3 COOH(aq) H + (aq) + CH 3 COO (aq) Initial (M): 0.40 0.00
More informationI II III IV. Volume HCl added. 1. An equation representing the reaction of a weak acid with water is
1. An equation representing the reaction of a weak acid with water is A. HCl + H 2 O H 3 O + + Cl B. NH 3 + H 2 O NH 4 + + OH C. HCO 3 H 2 O H 2 CO 3 + OH D. HCOOH + H 2 O H 3 O + + HCOO 2. The equilibrium
More informationAqueous Equilibria Pearson Education, Inc. Mr. Matthew Totaro Legacy High School AP Chemistry
2012 Pearson Education, Inc. Mr. Matthew Totaro Legacy High School AP Chemistry The Common-Ion Effect Consider a solution of acetic acid: HC 2 H 3 O 2 (aq) + H 2 O(l) H 3 O + (aq) + C 2 H 3 O 2 (aq) If
More informationChapter 8 Acid-Base Equilibria
Chapter 8 Acid-Base Equilibria 8-1 Brønsted-Lowry Acids and Bases 8-2 Water and the ph Scale 8-3 The Strengths of Acids and Bases 8-4 Equilibria Involving Weak Acids and Bases 8-5 Buffer Solutions 8-6
More informationChapter 17 Additional Aspects of
Chemistry, The Central Science, 11th edition Theodore L. Brown; H. Eugene LeMay, Jr.; and Bruce E. Bursten Chapter 17 Additional Aspects of John D. Bookstaver St. Charles Community College Cottleville,
More informationK A K B = K W pk A + pk B = 14
Relationship between the ionization constants of an acid and its conjugate base HCN (aq) H 2 O(l) CN (aq) H O (aq) Conjugate couple The product between of an acid and of its conjugate base is : p p 14
More informationACIDS AND BASES. for it cannot be But I am pigeon-liver d and lack gall To make oppression bitter Hamlet
ACIDS AND BASES for it cannot be But I am pigeon-liver d and lack gall To make oppression bitter Hamlet Learning objectives Name and write formulae for common acids and bases Describe acids and bases according
More informationCHAPTER 7 Acid Base Equilibria
1 CHAPTER 7 Acid Base Equilibria Learning Objectives Acid base theories Acid base equilibria in water Weak acids and bases Salts of weak acids and bases Buffers Logarithmic concentration diagrams 2 ACID
More informationCHAPTER 16 ACID-BASE EQUILIBRIA AND SOLUBILITY EQUILIBRIA
CHAPTER 16 ACID-BASE EQUILIBRIA AND SOLUBILITY EQUILIBRIA 16.5 (a) This is a weak acid problem. Setting up the standard equilibrium table: CH 3 COOH(aq) H (aq) CH 3 COO (aq) Initial (): 0.40 0.00 0.00
More informationCreate assignment, 48975, Exam 2, Apr 05 at 9:07 am 1
Create assignment, 48975, Exam 2, Apr 05 at 9:07 am 1 This print-out should have 30 questions. Multiple-choice questions may continue on the next column or page find all choices before making your selection.
More informationChapter 15 - Applications of Aqueous Equilibria
Neutralization: Strong Acid-Strong Base Chapter 15 - Applications of Aqueous Equilibria Molecular: HCl(aq) + NaOH(aq) NaCl(aq) + H 2 O(l) SA-SB rxn goes to completion (one-way ) Write ionic and net ionic
More information2] What is the difference between the end point and equivalence point for a monobasicmonoacid
4 Titrations modified October 9, 2013 1] A solution of 0.100 M AgNO 3 is used to titrate a 100.00 ml solution of 0.100 M KCl. The K sp of AgCl is 1.8e-11 a) What is pag if 50.00 ml of the titrant is added
More informationAP Chemistry. CHAPTER 17- Buffers and Ksp 17.1 The Common Ion Effect Buffered Solutions. Composition and Action of Buffered Solutions
AP Chemistry CHAPTER 17- Buffers and Ksp 17.1 The Common Ion Effect The dissociation of a weak electrolyte is decreased by the addition of a strong electrolyte that has an ion in common with the weak electrolyte.
More informationAcid - Base Equilibria 3
Acid - Base Equilibria 3 Reading: Ch 15 sections 8 9 Ch 16 sections 1 7 * = important homework question Homework: Chapter 15: 97, 103, 107, Chapter 16: 29*, 33*, 35, 37*, 39*, 41, 43*, 49, 55, 57, 61,
More informationph calculations MUDr. Jan Pláteník, PhD Brønsted-Lowry concept of acids and bases Acid is a proton donor Base is a proton acceptor
ph calculations MUDr. Jan Pláteník, PhD Brønsted-Lowry concept of acids and bases Acid is a proton donor Base is a proton acceptor HCl(aq) + H 2 O(l) H 3 O + (aq) + Cl - (aq) Acid Base Conjugate acid Conjugate
More informationCHAPTER 8: ACID/BASE EQUILIBRIUM
CHAPTER 8: ACID/BASE EQUILIBRIUM Already mentioned acid-base reactions in Chapter 6 when discussing reaction types. One way to define acids and bases is using the Brønsted-Lowry definitions. A Brønsted-Lowry
More informationEquilibrium constant
Equilibrium constant Equilibrium constant Many reactions that occur in nature are reversible and do not proceed to completion. They come to an equilibrium where the net velocity = 0 The velocity of forward
More informationBuffer Solutions. Buffer Solutions
Buffer Solutions A buffer solution is comprised of a mixture of an acid (base) with its conjugate base (acid) that resists changes in ph when additional acid or base is added The Henderson-Hasselbalch
More informationProblem 1 C 6 H 5 [ COOH C 6 H[H 5 COO + ] - + H [ I C - x + x + x E x x x
Problem 1 What is the ph of a 291mL sample of 2.993M benzoic acid (C 6 H 5 COOH) (K a =6.4x10 5 )? Write out acid dissociation reaction: C 6 H 5 COOH C 6 H 5 COO H Make an ICE chart since this is a weak
More informationCHEMISTRY - MCQUARRIE 4E CH.21 - BUFFERS & THE TITRATION OF ACIDS & BASES
!! www.clutchprep.com CONCEPT: CLASSIFICATION AND IDENTIFICATION OF BUFFERS Solutions which contain a acid and its base are called buffer solutions because they resist drastic changes in ph. They resist
More information