KEY. Practice Problems: Applications of Aqueous Equilibria

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "KEY. Practice Problems: Applications of Aqueous Equilibria"

Transcription

1 Practice Problems: Applications of Aqueous Equilibria KEY CHEM 1B 1. Ammonia (NH 3 ) is a weak base with a K b = 1.8 x 1 5. a) Write the balanced chemical equation for the reaction of ammonia with water. Using the I.C.E. method, calculate the ph and % ionization of a 1.75 M NH 3 solution in 2.5 M NH Cl. NH 3 (aq) + H 2 O (l) NH + (aq) + OH (aq) I C X +X +X E 1.75 X X X K b = [NH + ] [OH ] [NH 3 ] X = 1.26 x 1 5 M assume X is negligible (2.5+X) (X) 2.5X = = 1.8 x 1 5 (1.75 X) 1.75 assume X is negligible Check (% ionization): X [NH 3 ] (1%) 1.26 x 1 = init 1.75 M 5 M [OH ] eq = X = 1.26 x 1 5 M OH poh = log [OH ] poh = log (1.26 x 1 5 M) poh = ph + POH = 1 ph = 9.1 (1%) =.72 % ionization assumption okay (<5%) b) How would the % ionization and ph have been different without the NH Cl? What is this effect called? The % ionization would be larger / smaller (circle one), and the ph would be higher / lower (circle one) common ion effect without the. c) Is this solution a buffer? Explain. Yes, this solution is a buffer, because it contains a weak acid - weak base conjugate pair. d) Other than with the ICE method, how else could you have solved this problem? using the Henderson-Hasselbalch equation Method:

2 2. A buffer is made from acetic acid (HC 2 H 3 O 2 ) and sodium acetate (NaC 2 H 3 O 2 ). 1.5 moles of acetic acid and 2.5 moles of sodium acetate are added to enough water to make 1.5 liter of solution. The ionization constant (K a ) for acetic acid is 1.8 x 1 5. a) Write the equation for the ionization of acetic acid in water, and using a stress-shiftequilibrium arrow diagram, show how the buffer would minimize the effect of adding a base to the solution. Stress: Shift: Equilibrium: HC 2 H 3 O 2 (aq) b) Using the Henderson-Hasselbalch equation, find the ph of this buffer solution. ph = pk a + log H + (aq) + C 2 H 3 O 2 (aq) [base] [acid] [C 2 H 3 O 2 ] ph = pk a + log [HC 2 H 3 O 2 ] (2.5 mol / 1.5 L) ph = log (1.8 x 1 5 ) + log (1.5 mol / 1.5 L) ph = = ph =.97 Note: Assume no ionization (a good assumption due to the common ion effect). Also note: The volume of the solution cancels out. Dilution does not affect the ph of a buffer! c) Calculate the percent ionization of the acetic acid in this solution. ph = log [H + ] [H + ] = 1 ph [H + ] = = 1.8 x 1 5 M H + % ionization = [H + ] eq [HC 2 H 3 O 2 ] init 1.8 x 1 5 M H + (1%) = 1. M HC 2 H 3 O 2 (1%) =.18 % ionization.11 % ionization d) At what ph would this solution have the largest buffering capacity in both directions? [base] ph soln = pk a + log [acid] ph soln = log (1.8 x 1 5 ) + ph =.7 Note: Buffering capacity is maximized in both directions when [acid] = [base]. log (1) =

3 3. Based on the titration curve to the right and the tables of K a values below, determine the following: a) The most appropriate indicator for the titration. ph (at eq. pt.) = pk a ind = 9.3 K a ind = 1 pka = = 5 x 1 1 Phenolphthalein b) Whether the unknown acid is a strong acid or a weak acid (circle one). How do you know? ph (at eq. pt.) > 7 c) The most likely identity of the unknown acid. ph (at ½ eq. pt.) = pk a unk =.8 K a unk = 1 pka = 1.8 = 2 x 1 5 acetic acid ph d) The original concentration of the 1. ml sample of unknown monoprotic acid. (1) M a (1. ml) = (1) (.5 M) (12. ml) M a =.6 M acetic acid 1 Titration of 1. ml of an 13 Unknown Acid ml of.5 M NaOH added Indicator K a Metacresol Purple 3.1 x1 2 Thymol Blue 2.2 x 1 2 Methyl Orange 3.5 x 1 Bromophenol Blue 7.9 x 1 5 Bromocresol Green 1.3 x 1 5 Methyl Red 1. x 1 5 Chlorophenol Red 5.6 x 1 7 Bromocresol Purple. x 1 7 Bromothymol Blue 5. x 1 8 Cresol Red 3.5 x 1 9 Phenolphthalein 3 x 1 1 Acid K a chlorous acid 1.2 x 1 2 hydrofluoric acid 7.2 x 1 nitrous acid. x 1 lactic acid 1.38 x 1 benzoic acid 6. x 1 5 acetic acid 1.8 x 1 5 hypochlorous acid 3.5 x 1 8 ammonium ion 5.6 x 1 1

4 1 Titration of 25. ml of an Unknown Diprotic Acid ph 12 F 1 E 8 D 6 2 A B C ml of.1 M NaOH added. Based on the titration curve for a diprotic acid above, answer the following: a) Identify in the table to the right which species exist in solution at each point on the curve (using H 2 A to represent a generic diprotic acid). b) Given the table of ionization constants, identify the unknown acid. ph (at 1st ½ eq. pt.) = pk a1 unk = 1.8 K a1 unk = 1 pka1 = = 2 x 1 2 Point A B C D E F Species from the unknown H 2 A H 2 A, HA HA HA, A 2 A 2 A 2 Species from the titrant, OH ph (at 2nd ½ eq. pt.) = pk a2 unk = 7. K a2 unk = 1 pka2 = 1 7. = 1 x 1 7 sulfurous acid c) Calculate the concentration of the original diprotic acid solution. Acid K a1 K a2 oxalic acid 6.5 x x 1 5 sulfurous acid 1.5 x x 1 7 ascorbic acid 7.9 x x 1 12 carbonic acid.3 x x 1 11 Note: The 2 nd eq. pt. is a better choice since it is sharper (making estimating more precise), and has a larger volume (making estimating errors proportionally smaller). From the first equivalence point (1) M a (25. ml) = (1) (.1 M) (7. ml) M a =.28 M sulfurous acid From the second equivalence point (2) M a (25. ml) = (1) (.1 M) (1. ml) M a =.28 M sulfurous acid 1 H + neutralized both H + neutralized

5 5. Based on the titration curve to the right and the tables of K b values below, determine the following: a) The most appropriate indicator for the titration. ph (at eq. pt.) = pk a ind = 5.2 K a ind = 1 pka = = 6 x 1 6 Methyl Red b) Whether the unknown base is a strong base or a weak base (circle one). How do you know? ph (at eq. pt.) < 7 c) The most likely identity of the unknown base. ph (at ½ eq. pt.) = pk a unk. conj. acid = = pk a + pk b pk b unk =.2 K b unk = 1 pkb = 1.2 = 6 x 1 5 trimethylamine ph d) The original concentration of the 15. ml sample of unknown base. (1) (.25 M) (1. ml) = (1) M b (15. ml) M b =.23 M trimethylamine 1 Titration of 15. ml of an 13 Unknown Base ml of.25 M HCl added Indicator K a Metacresol Purple 3.1 x1 2 Thymol Blue 2.2 x 1 2 Methyl Orange 3.5 x 1 Bromophenol Blue 7.9 x 1 5 Bromocresol Green 1.3 x 1 5 Methyl Red 1. x 1 5 Chlorophenol Red 5.6 x 1 7 Bromocresol Purple. x 1 7 Bromothymol Blue 5. x 1 8 Cresol Red 3.5 x 1 9 Phenolphthalein 3 x 1 1 Base K b ethylamine 6. x 1 dimethylamine 5. x 1 methylamine 3.7 x 1 trimethylamine 6.5 x 1 5 ammonia 1.8 x 1 5 hydroxylamine 9.1 x 1 9 phenylamine.3 x 1 1

6 6. The K sp of silver chromate (Ag 2 CrO ) is 1.9 x a) Write the balanced complete ionic equation for the dissociation of Ag 2 CrO. b) Using the I.C.E. method and the equilibrium expression, find the molar solubility of Ag 2 CrO. (Hint: you are solving for X) Ag 2 CrO (s) 2 Ag + (aq) + CrO 2 (aq) Initial Conc. Change in Conc. X +2X +X Equilib. Conc. 2X X K sp = [Ag + ] 2 [CrO 2 ] = (2X) 2 (X) K sp = X x 1 12 = X 3 X = 1.9 x 1 12 ( 1 / 3 ) = 7.8 x 1 5 M 7.8 x 1 5 M Ag 2 CrO 7. The molar solubility of chromium (III) hydroxide in water at 25 C is 1.26 x 1 8 M Cr(OH) 3. a) Write the balanced complete ionic equation for the dissociation of Cr(OH) 3. b) Using the I.C.E. method and the equilibrium expression, find the K sp of Cr(OH) 3. Cr(OH) 3 (s) Cr 3+ (aq) + 3 OH (aq) Initial Conc. Change in Conc. X +X +3X Equilib. Conc. X 3X K sp = [Cr 3+ ] [OH ] 3 = (X) (3X) 3 K sp = 27X K sp = 27(1.26 x 1 8 M) K sp = x 1 31 = 6.81 x The molar solubilities of two ionic compounds can be directly compared, but not always the K sp values. Circle the two compounds for which the K sp values could be compared and indicate which one of the two is more soluble in water. # ions: 1 & 1 1 & 2 3 & 2 2 & 1 1 & 3 PbCrO Mg(OH) 2 Cu 3 (PO ) 2 Ag 2 SO Al(OH) 3 K sp = 2.8 x 1 13 K sp = 5.6 x 1 12 K sp = 1. x 1 37 K sp = 1.2 x 1 5 K sp = 1.9 x 1 33 more soluble

CHEM 102: Sample Test 5

CHEM 102: Sample Test 5 CHEM 102: Sample Test 5 CHAPTER 17 1. When H 2 SO 4 is dissolved in water, which species would be found in the water at equilibrium in measurable amounts? a. H 2 SO 4 b. H 3 SO + 4 c. HSO 4 d. SO 2 4 e.

More information

Solutions to Homework Assignment 11 CHM 152 Spring 2002

Solutions to Homework Assignment 11 CHM 152 Spring 2002 Solutions to Homework Assignment 11 CHM 152 Spring 2002 16.21 Since the acid is monoprotic, the number of moles of KOH is equal to the number of moles of acid. Moles acid = 16.4 ml 1 L 0.08133 mol = 0.00133

More information

Buffer Solutions. Chapter 16 Additional Aqueous Equilibria. Buffer Action. Buffer Action. The ph of Buffer Solutions.

Buffer Solutions. Chapter 16 Additional Aqueous Equilibria. Buffer Action. Buffer Action. The ph of Buffer Solutions. Buffer Solutions John W. Moore Conrad L. Stanitski Peter C. Jurs http://academic.cengage.com/chemistry/moore Chapter 16 Additional Aqueous Equilibria Buffer = chemical system that resists changes in ph.

More information

AMHS AP Chemistry Multiple Choice questions

AMHS AP Chemistry Multiple Choice questions 1 Aqueous Equilibria: Buffers & Titrations AMHS AP Chemistry Multiple Choice questions Name Common-Ion Effect 1) The ph of a solution that contains 0.818 M acetic acid (K a = 1.77x10-5 ) and 0.172 M sodium

More information

1. For the equilibrium that exists in an aqueous solution of nitrous acid (HNO 2, a weak acid), the equilibrium constant expression is:

1. For the equilibrium that exists in an aqueous solution of nitrous acid (HNO 2, a weak acid), the equilibrium constant expression is: 1. For the equilibrium that exists in an aqueous solution of nitrous acid (HNO 2, a weak acid), the equilibrium constant expression is: a) K = [H+ ][NO 2 ] [HNO 2 ] b) K = [H+ ][N][O] 2 [HNO 2 ] c) K =

More information

Buffer Solutions. Buffer Solutions

Buffer Solutions. Buffer Solutions Chapter 18 Common Ion Effect Buffers and Titration Curves A/B Titrations Salts and Solubility Product The Common Ion Effect and If a solution is made in which the same ion is produced by two different

More information

WEAK ACIDS AND BASES

WEAK ACIDS AND BASES WEAK ACIDS AND BASES [MH5; Chapter 13] Recall that a strong acid or base is one which completely ionizes in water... In contrast a weak acid or base is only partially ionized in aqueous solution... The

More information

CH302 Exam 4 Practice Problems (buffers, titrations, Ksp)

CH302 Exam 4 Practice Problems (buffers, titrations, Ksp) CH302 Exam 4 Practice Problems (buffers, titrations, Ksp) 1 Equilibrium Constants The following equilibrium constants will be useful for some of the problems. Substance Constant Substance Constant HCO

More information

AP FREE RESPONSE QUESTIONS ACIDS/BASES

AP FREE RESPONSE QUESTIONS ACIDS/BASES AP FREE RESPONSE QUESTIONS ACIDS/BASES 199 D A chemical reaction occurs when 100. milliliters of 0.200molar HCl is added dropwise to 100. milliliters of 0.100molar Na 3 P0 solution. (a) Write the two net

More information

Solubility Equilibria

Solubility Equilibria Chapter 17: Acid-Base Equilibria and Solubility Equilibria Key topics: Common ion effect Buffers Acid-base equilibria Solubility equilibria; complex ion formation The Common Ion Effect If we have two solutes

More information

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory.

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory. Acid-base A4 1 Acid-base theories ACIDS & BASES - IONIC EQUILIBRIA 1. LEWIS acid electron pair acceptor H, AlCl 3 base electron pair donor NH 3, H 2 O, C 2 H 5 OH, OH e.g. H 3 N: -> BF 3 > H 3 N BF 3 see

More information

AP Chemistry- Acids and Bases General Properties of Acids and Bases. Bases- originally defined as any substance that neutralized an acid

AP Chemistry- Acids and Bases General Properties of Acids and Bases. Bases- originally defined as any substance that neutralized an acid AP Chemistry Acids and Bases General Properties of Acids and Bases Acids Electrolyte Taste Litmus Phenolphthalein React with metals to give off H 2 gas H 2 SO 4 (aq) + Mg (s) MgSO 4 (aq) + H 2 (g) Ionize

More information

Acid-Base Equilibria and Solubility Equilibria

Acid-Base Equilibria and Solubility Equilibria Acid-Base Equilibria and Solubility Equilibria Chapter 16 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 The common ion effect is the shift in equilibrium

More information

Equilibrium Constants The following equilibrium constants will be useful for some of the problems.

Equilibrium Constants The following equilibrium constants will be useful for some of the problems. 1 CH302 Exam 4 Practice Problems (buffers, titrations, Ksp) Equilibrium Constants The following equilibrium constants will be useful for some of the problems. Substance Constant Substance Constant HCO

More information

Buffer Solutions. Buffer Solutions

Buffer Solutions. Buffer Solutions Buffer Solutions ph of solution adding 0.10 M HCl to 100 ml water HCl added ph 0 ml 7.00 2 ml 2.71 5 ml 2.32 10 ml 2.04 20 ml 1.78 50 ml 1.48 7 6 5 4 3 2 1 0 10 20 30 40 50 ml of 0.10 M HCl added Buffer

More information

Chapter 17. The best buffer choice for ph 7 is NaH 2 PO 4 /Na 2 HPO 4. 19)

Chapter 17. The best buffer choice for ph 7 is NaH 2 PO 4 /Na 2 HPO 4. 19) Chapter 17 2) a) HCl and CH 3 COOH are both acids. A buffer must have an acid/base conjugate pair. b) NaH 2 PO 4 and Na 2 HPO 4 are an acid/base conjugate pair. They will make an excellent buffer. c) H

More information

CHEM 36 General Chemistry EXAM #3 April 17, 2002

CHEM 36 General Chemistry EXAM #3 April 17, 2002 CHEM 36 General Chemistry EXAM #3 April 17, 2002 Name: Anne Sir Kei INSTRUCTIONS: Read through the entire exam before you begin. Answer all of the questions. For questions involving calculations, show

More information

CHEM 102 CLASS NOTES Prof. Upali Siriwardane, Chemistry Program, Louisiana Tech University, Ruston, LA CHAPTER 17 KEY CONCEPTS

CHEM 102 CLASS NOTES Prof. Upali Siriwardane, Chemistry Program, Louisiana Tech University, Ruston, LA CHAPTER 17 KEY CONCEPTS CHEM 102 CLASS NOTES Prof. Upali Siriwardane, Chemistry Program, Louisiana Tech University, Ruston, LA 71272 CHAPTER 17 KEY CONCEPTS ph for buffer solutions concentration of ions in buffer solutions ph

More information

Chem 321 Lecture 13 - Acid-Base Titrations 10/10/13

Chem 321 Lecture 13 - Acid-Base Titrations 10/10/13 Student Learning Objectives Chem 321 Lecture 13 - Acid-Base Titrations 10/10/13 Indicators A common end point for acid-base titrations is the color change associated with an acid-base indicator. An acid-base

More information

CHM1 Review for Exam 12

CHM1 Review for Exam 12 Topics Solutions 1. Arrhenius Acids and bases a. An acid increases the H + concentration in b. A base increases the OH - concentration in 2. Strong acids and bases completely dissociate 3. Weak acids and

More information

Chapter 7 Mixtures of Acids and Bases

Chapter 7 Mixtures of Acids and Bases Chapter 7 Mixtures of Acids and Bases Introduction In Chapter 6, we examined the equilibrium concentrations in solutions of acids and solutions of bases. In this chapter, we continue our discussion of

More information

Copyright 2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved.

Copyright 2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved. Sample Exercise 17.1 Calculating the ph When a Common Ion is Involved What is the ph of a solution made by adding 0.30 mol of acetic acid and 0.30 mol of sodium acetate to enough water to make 1.0 L of

More information

Chapter 16: Acid-Base Equilibria

Chapter 16: Acid-Base Equilibria Chapter 16: Acid-Base Equilibria In the 1 st half of this chapter we will focus on the equilibria that exist in aqueous solutions containing: weak acids polyprotic acids weak bases salts use equilibrium

More information

ph: Measurement and Uses

ph: Measurement and Uses ph: Measurement and Uses One of the most important properties of aqueous solutions is the concentration of hydrogen ion. The concentration of H + (or H 3 O + ) affects the solubility of inorganic and organic

More information

Chapter 19: Acids and Bases Homework Packet (50 pts) Name: Score: / 50

Chapter 19: Acids and Bases Homework Packet (50 pts) Name: Score: / 50 Chapter 19: Acids and Bases Homework Packet (50 pts) Topic pg Section 19.1 1-3 Section 19.2 3-6 Section 19.3 6-7 Section 19.4 8 Naming Acids 9 Properties of Acids/Bases 10-11 Conjugate Acid/Base Pairs

More information

Name period Unit 9: acid/base equilibrium

Name period Unit 9: acid/base equilibrium Name period Unit 9: acid/base equilibrium 1. What is the difference between the Arrhenius and the BronstedLowry definition of an acid? Arrhenious acids give H + in water BronstedLowry acids are proton

More information

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory.

Q.1 Classify the following according to Lewis theory and Brønsted-Lowry theory. Acid-base 2816 1 Acid-base theories ACIDS & BASES - IONIC EQUILIBRIA LEWIS acid electron pair acceptor H +, AlCl 3 base electron pair donor NH 3, H 2 O, C 2 H 5 OH, OH e.g. H 3 N: -> BF 3 > H 3 N + BF

More information

Answer the following questions on notebook paper, to be collected and graded for correctness.

Answer the following questions on notebook paper, to be collected and graded for correctness. nswer the following questions on notebook paper, to be collected and graded for correctness. 1. Name the following binary acids: a. HCl hydrochloric acid b. HF hydrofluoric acid c. H 2 S hydrosulfuric

More information

1. Identify the Bronsted-Lowry acids and bases and the conjugate acid base pairs in the following reactions.

1. Identify the Bronsted-Lowry acids and bases and the conjugate acid base pairs in the following reactions. Exercise #1 Brønsted-Lowry s and Bases 1. Identify the Bronsted-Lowry acids and bases and the conjugate acid base pairs in the following reactions. (a) HCl(aq) + H 2 O(l) H 3 O + (aq) + Cl (aq) (b) H 2

More information

Chemical equilibria Buffer solutions

Chemical equilibria Buffer solutions Chemical equilibria Buffer solutions Definition The buffer solutions have the ability to resist changes in ph when smaller amounts of acid or base is added. Importance They are applied in the chemical

More information

Chapter 16 Acid-Base Equilibria and Solubility Equilibria

Chapter 16 Acid-Base Equilibria and Solubility Equilibria Chapter 16 Acid-Base Equilibria and Solubility Equilibria Student: NOTE: A table of ionization constants and K a 's is required to work some of the problems in this chapter. 1. In which one of the following

More information

Chapter 21 Buffers and the titration of Acids and Bases Shuffle order make 21-3 last!

Chapter 21 Buffers and the titration of Acids and Bases Shuffle order make 21-3 last! Chapter 21 Buffers and the titration of Acids and Bases Shuffle order make 213 last! 211 The HendersonHasselbalch Equation What happens when you mix an acid and its own conjugate base? Using an acetic

More information

Lecture 6. Classes of Chemical Reactions

Lecture 6. Classes of Chemical Reactions Lecture 6 Classes of Chemical Reactions Lecture 6 Outline 6.1 The Role of Water as a Solvent 6.2 Precipitation Reactions 6.3 Acid-Base Reactions 1 Electron distribution in molecules of H 2 and H 2 O The

More information

CHAPTER 16. ACID-BASE EQUILIBRIA

CHAPTER 16. ACID-BASE EQUILIBRIA 16.2 COMMON ION EFFECT CHAPTER 16. ACID-BASE EQUILIBRIA common ion effect: The shift in equilibrium caused by the addition of a substance having an ion in common with the equilibrium mixture. Addition

More information

Titration curves. Strong Acid-Strong Base Titrations

Titration curves. Strong Acid-Strong Base Titrations Titration curves A titration is a procedure for carrying out a chemical reaction between two solutions by the controlled addition from a buret of one solution (the titrant) to the other, allowing measurements

More information

CHEM 10123/10125, Exam 2

CHEM 10123/10125, Exam 2 CHEM 10123/10125, Exam 2 March 7, 2012 (50 minutes) Name (please print) Please box your answers, and remember that significant figures, phases (for chemical equations), and units do count! 1. (13 points)

More information

VONDRACEK WKS 13.1 Conjugates Using Brönsted-Lowry s Definition (2 pages)

VONDRACEK WKS 13.1 Conjugates Using Brönsted-Lowry s Definition (2 pages) VONDRACEK WKS 13.1 Conjugates Using Brönsted-Lowry s Definition (2 pages) Give the conjugate acid of the following bases: BASE CONJUGATE ACID BASE CONJUGATE ACID H2O ClO acetate H2PO4 NH3 HSO4 hydroxide

More information

Name: Per: Date: Unit 11 - Acids, Bases and Salts Chemistry Accelerated Chemistry I Define each of the following: 1. Acidic hydrogens.

Name: Per: Date: Unit 11 - Acids, Bases and Salts Chemistry Accelerated Chemistry I Define each of the following: 1. Acidic hydrogens. Name: Per: Date: Unit 11 - Acids, Bases and Salts Chemistry Accelerated Chemistry I Define each of the following: 1. Acidic hydrogens 2. Binary acids 3. Oxyacids 4. Carboxylic acid 5. Amines Name the following

More information

Acid-Base Equilibrium

Acid-Base Equilibrium AcidBaseEquil 1 Acid-Base Equilibrium See AqueousIons in Chemistry 1110 online notes for review of acid-base fundamentals! Acid- Base Reaction in Aqueous Salt Solutions Recall that use [ ] to mean concentration

More information

Chapter 16. Acid-Base Equilibria and Solubility Equilibria

Chapter 16. Acid-Base Equilibria and Solubility Equilibria Chapter 16. Acid-Base Equilibria and Solubility Equilibria What we will learn: Homogeneous and heterogeneous solution equilibria Common ion effect Buffer solutions Acid-base titrations Acid-base indicators

More information

4. Acid Base Equilibria

4. 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 information

Acid/Base Definition. Acid/Base Reactions. Major vs. Minor Species. Terms/Items you Need to Know. you need to memorize these!!

Acid/Base Definition. Acid/Base Reactions. Major vs. Minor Species. Terms/Items you Need to Know. you need to memorize these!! Acid/Base Reactions some covalent compounds have weakly bound H atoms and can lose them to water (acids) some compounds produce OH in water solutions when they dissolve (bases) acid/base reaction are very

More information

Topic 18 Acids and Bases. 18.1 Exercises

Topic 18 Acids and Bases. 18.1 Exercises Topic 18 Acids and Bases 18.1 Exercises 1. Define: (a) ph The negative log of the hydrogen ion concentration in a solution. i.e. ph = log[h 3 O + ] (b) poh The negative log of hydroxide ion concentration

More information

UNIT 14 - Acids & Bases

UNIT 14 - Acids & Bases COMMON ACIDS NOTES lactic acetic phosphoric citric malic PROPERTIES OF ACIDS 1. 1. PROPERTIES OF BASES 2. 2. 3. 3. 4. 4. 5. 5. NAMING ACIDS NOTES Binary acids (H + one element) Practice: 1. hydro- - HF

More information

ph. Weak acids. A. Introduction

ph. Weak acids. A. Introduction ph. Weak acids. A. Introduction... 1 B. Weak acids: overview... 1 C. Weak acids: an example; finding K a... 2 D. Given K a, calculate ph... 3 E. A variety of weak acids... 5 F. So where do strong acids

More information

Chapters 6 and 8. Systematic Treatment of Equilibrium

Chapters 6 and 8. Systematic Treatment of Equilibrium Chapters 6 and 8 Systematic Treatment of Equilibrium Equilibrium constants may be written for dissociations, associations, reactions, or distributions. Gary Christian, Analytical Chemistry, 6th Ed. (Wiley)

More information

Acid - Base page 1. K a = = [H+ ][CH 3 COO ] [CH 3 COOH] [H + ] = [CH 3 COO ] = X [CH 3 COOH] = 2.0 X, X << 2.0, (2.0 X) = 2.

Acid - Base page 1. K a = = [H+ ][CH 3 COO ] [CH 3 COOH] [H + ] = [CH 3 COO ] = X [CH 3 COOH] = 2.0 X, X << 2.0, (2.0 X) = 2. 1970 (a) What is the ph of a 2.0 molar solution of acetic acid. K a acetic acid = 1.8 10 5 (b) A buffer solution is prepared by adding 0.10 liter of 2.0 molar acetic acid solution to 0.1 liter of a 1.0

More information

Chemistry 212 EXAM 2 February 17, 2004 KEY

Chemistry 212 EXAM 2 February 17, 2004 KEY 1 Chemistry 212 EXAM 2 February 17, 2004 100_ (of 100) KEY Name Part 1: Multiple Choice. (1 point 4. The equilibrium constant for the each, circle only one answer, reaction 1. For the equilibrium that

More information

Chem 116 POGIL Worksheet - Week 10 - Solutions Weak Acid and Base Equilibria

Chem 116 POGIL Worksheet - Week 10 - Solutions Weak Acid and Base Equilibria Chem 116 POGIL Worksheet - Week 10 - Solutions Weak Acid and Base Equilibria Key Questions 1. A 0.0100 M solution of a weak acid HA has a ph of 2.60. What is the value of K a for the acid? [Hint: What

More information

17B. An Acid Base Titration Curve

17B. An Acid Base Titration Curve 17B. An Acid Base Titration Curve Time: 2 hours Required chemicals and solutions: Reagent Requirement/5 Pairs Preparation of 1 L Potassium hydrogen phthalate 5.1 g NaOH, 0.1 M 250 ml 4.0 g of NaOH Other

More information

D. Combustion Reaction CxHy + O 2 CO 2 + H 2 O Example: i) C 4 H 10 + O 2 CO 2 + H 2 O. ii) C 6 H 12 O 6 + O 2 CO 2 + H 2 O

D. Combustion Reaction CxHy + O 2 CO 2 + H 2 O Example: i) C 4 H 10 + O 2 CO 2 + H 2 O. ii) C 6 H 12 O 6 + O 2 CO 2 + H 2 O 1 A. Combination Reaction A + B AB i) SO 3 + H 2 O H 2 SO 4 ii) P + S P 2 S 5 iii) N 2 + H 2 NH 3 B. Decomposition Reaction AB A + B i) H 2 CO 3 H 2 O + CO 2 ii) KClO 3 KCl + O 2 C. Single Displacement

More information

UNIT (6) ACIDS AND BASES

UNIT (6) ACIDS AND BASES UNIT (6) ACIDS AND BASES 6.1 Arrhenius Definition of Acids and Bases Definitions for acids and bases were proposed by the Swedish chemist Savante Arrhenius in 1884. Acids were defined as compounds that

More information

Acids and Bases: Definitions. Brønsted-Lowry Acids and Bases. Brønsted-Lowry Acids and Bases CHEMISTRY THE CENTRAL SCIENCE

Acids and Bases: Definitions. Brønsted-Lowry Acids and Bases. Brønsted-Lowry Acids and Bases CHEMISTRY THE CENTRAL SCIENCE CHEMISTRY THE CENTRAL SCIENCE Professor Angelo R. Rossi Department of Chemistry Spring Semester Acids and Bases: Definitions Arrhenius Definition of Acids and Bases Acids are substances which increase

More information

We remember that molarity (M) times volume (V) is equal to moles so this relationship is the definition of the equivalence point.

We remember that molarity (M) times volume (V) is equal to moles so this relationship is the definition of the equivalence point. Titrations Titration - a titration is defined as the determination of the amount of an unknown reagent (analyte) through the use of a known amount of another reagent (titrant) in an essentially irreversible

More information

Name: Class: Date: 2 4 (aq)

Name: Class: Date: 2 4 (aq) Name: Class: Date: Unit 4 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The balanced molecular equation for complete neutralization of

More information

Titrations. Acid-Base Indicators and Titration Curves. Shapes of Titration Curves. A titration curve is a graphical history of a titration

Titrations. Acid-Base Indicators and Titration Curves. Shapes of Titration Curves. A titration curve is a graphical history of a titration Acid-Base Indicators and Titration Curves Titrations In a titration a solution of accurately known concentration is added gradually added to another solution of unknown concentration until the chemical

More information

CHAPTERS 15 FAKE TEST QUESTIONS. 1. According to the Brønsted Lowry definition, which species can function both as an acid and as a base?

CHAPTERS 15 FAKE TEST QUESTIONS. 1. According to the Brønsted Lowry definition, which species can function both as an acid and as a base? You might need to know the following K values: CHAPTERS 15 FAKE TEST QUESTIONS CH 3 COOH K a = 1.8 x 10 5 Benzoic Acid K a = 6.5 x 10 5 HNO 2 K a = 4.5 x 10 4 NH 3 K b = 1.8 x 10 5 HF K a = 7.2 x 10 4

More information

Acids, Bases, Salts, and Buffers

Acids, Bases, Salts, and Buffers Acids, Bases, Salts, and Buffers GOAL AND OVERVIEW Hydrolysis of salts will be used to study the acid-base properties of dissolved ions in aqueous solutions. The approximate ph of these solutions will

More information

General Chemistry II Chapter 20

General Chemistry II Chapter 20 1 General Chemistry II Chapter 0 Ionic Equilibria: Principle There are many compounds that appear to be insoluble in aqueous solution (nonelectrolytes). That is, when we add a certain compound to water

More information

Acids and Bases. Ch a pt e r Aqueous Equilibria: Chemistry 4th Edition McMurry/Fay. MOH(aq) M + (aq) + OH (aq)

Acids and Bases. Ch a pt e r Aqueous Equilibria: Chemistry 4th Edition McMurry/Fay. MOH(aq) M + (aq) + OH (aq) 15 Ch a pt e r Aqueous Equilibria: Acids and Bases Chemistry th Edition McMurry/Fay Dr. Paul Charlesworth Michigan Technological University AcidBase Concepts 01 Arrhenius Acid: A substance which dissociates

More information

Review for Solving ph Problems:

Review for Solving ph Problems: Review for Solving ph Problems: Acid Ionization: HA H 2 O A - H 3 O CH 3 COOH H 2 O CH 3 COO - H 3 O Base Ionization: B H 2 O BH OH - 1) Strong Acid complete dissociation [H ] is equal to original [HA]

More information

6) Which compound is manufactured in larger quantities in the U.S. than any other industrial chemical?

6) Which compound is manufactured in larger quantities in the U.S. than any other industrial chemical? MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which statement concerning Arrhenius acid-base theory is not correct? A) Acid-base reactions must

More information

In general: the solubility product is the molar concentration of ions raised to their stoichiometric powers.

In general: the solubility product is the molar concentration of ions raised to their stoichiometric powers. 1 hapter 17 Additional Aspects of Aqueous Equilibria I. Solubility Equilibria The solubility product constant K sp onsider BaSO 4 (s) X Ba 2+ (aq) + SO 4 2- (aq) for which K sp = [Ba 2+ ][SO 4 2- ] K sp

More information

ionic substances (separate) based on! Liquid Mixtures miscible two liquids that and form a immiscible two liquids that form a e.g.

ionic substances (separate) based on! Liquid Mixtures miscible two liquids that and form a immiscible two liquids that form a e.g. Unit 7 Solutions, Acids & Bases Solution mixture + solvent - substance present in the amount solute - in the solvent solvent molecules solute particles ionic substances (separate) based on! Liquid Mixtures

More information

16. What is the H 3 O + concentration of a solution that has an OH concentration of 1 10 3 M? 1) 1 10 4 M 3) 1 10 11 M

16. What is the H 3 O + concentration of a solution that has an OH concentration of 1 10 3 M? 1) 1 10 4 M 3) 1 10 11 M 1. If the [OH ] = 1 10 4 at 298 K for a given solution, the [H + ] of the solution is equal to 1) 1 10 14 3) 1 10 6 2) 1 10 10 4) 1 10 4 2. Based on Reference Table V, which is the strongest base? 1) NO

More information

HNO 3(aq) + NO (g) b) (1 pt) Would the equilibrium in reaction (b) be shifted to the right by raising or lowering the temperature?

HNO 3(aq) + NO (g) b) (1 pt) Would the equilibrium in reaction (b) be shifted to the right by raising or lowering the temperature? ) To make nitric acid (HN 3 ), in industry, the following process is used: NH 3(g) + 2(g) N (g) + H 2 (g) (a) N (g) + 2(g) N 2 (g) ΔH > 0 (b) N 2(g) + H 2 (l) HN 3(aq) + N (g) (c) a) (3 pts) Balance each

More information

Acid/base Definitions. Acid/Base Definitions. Acid / Base Chemistry. Acid/Base Definitions. Identifying Acids and Bases

Acid/base Definitions. Acid/Base Definitions. Acid / Base Chemistry. Acid/Base Definitions. Identifying Acids and Bases Acids Identifying Acids and Bases Acid (anhydrides) contains H+ ions as the cation, with and other element as the anion Non-metal oxide H2SO4 HI P2O5 Bases Base (anhydrides) Contains OH- as the anion Combined

More information

CHEM N-3 November Answer:

CHEM N-3 November Answer: CHEM1612 2013-N-3 November 2013 Calculate the molar solubility of silver sulfide, Ag 2 S, given that K sp is 8 10 51 at 25 C. 3 The dissolution reaction and solubility product are: Ag 2 S(s) 2Ag + (aq)

More information

Chapter 14 - Acids and Bases

Chapter 14 - Acids and Bases Chapter 14 - Acids and Bases 14.1 The Nature of Acids and Bases A. Arrhenius Model 1. Acids produce hydrogen ions in aqueous solutions 2. Bases produce hydroxide ions in aqueous solutions B. Bronsted-Lowry

More information

ph of strong acid and base

ph of strong acid and base ph of strong acid and base What does strong mean in terms of acids and bases? Solubility. Basically, if you say an acid or base is strong, then it dissociates 100% in water. These types of situations are

More information

The Advanced Placement Examination in Chemistry. Acid Base

The Advanced Placement Examination in Chemistry. Acid Base The Advanced Placement Examination in Chemistry Part II Free Response Questions & Answers 1970 to 2009 Acid Base Teachers may reproduce this publication, in whole or in part, in limited print quantities

More information

V. POLYPROTIC ACID IONIZATION. NOTICE: K a1 > K a2 > K a3 EQUILIBRIUM PART 2. A. Polyprotic acids are acids with two or more acidic hydrogens.

V. POLYPROTIC ACID IONIZATION. NOTICE: K a1 > K a2 > K a3 EQUILIBRIUM PART 2. A. Polyprotic acids are acids with two or more acidic hydrogens. EQUILIBRIUM PART 2 V. POLYPROTIC ACID IONIZATION A. Polyprotic acids are acids with two or more acidic hydrogens. monoprotic: HC 2 H 3 O 2, HCN, HNO 2, HNO 3 diprotic: H 2 SO 4, H 2 SO 3, H 2 S triprotic:

More information

14-Jul-12 Chemsheets A

14-Jul-12 Chemsheets A www.chemsheets.co.uk 14-Jul-12 Chemsheets A2 009 1 BRONSTED-LOWRY ACIDS & BASES Bronsted-Lowry acid = proton donor (H + = proton) Bronsted-Lowry base = proton acceptor (H + = proton) Bronsted-Lowry acid-base

More information

2. Write a balanced chemical equation which corresponds to the following equilibrium constant expression. 1/2 3/ 2

2. Write a balanced chemical equation which corresponds to the following equilibrium constant expression. 1/2 3/ 2 Practice Problems for Chem. 1B Exam 1 F2011 These represent the concepts covered for exam 1. There may be some additional net ionic equations from chem. 1A. This is not the exact exam! Sections 16.1-16.3

More information

(last revised 2013 Sep 12)

(last revised 2013 Sep 12) Biology/Chemistry 302 -- Biochemistry (last revised 2013 Sep 12) Aqueous equilibria and buffer construction Goals: Making solutions 1) Given a periodic table, you should be able to calculate the number

More information

stronger than the attraction of the water to either the Pb 2+ or SO 4

stronger than the attraction of the water to either the Pb 2+ or SO 4 Reactions in solution Precipitation reactions not all ionic compounds are soluble in water. If PbSO 4 is added to water none of the lead(ii)sulfate will dissolve (the interaction between Pb 2+ and SO 4

More information

Acid-Base 2/27/2012. Definitions of Acids/Bases. Acid-Base Behavior. Arrhenius Definition. Arrhenius Definition

Acid-Base 2/27/2012. Definitions of Acids/Bases. Acid-Base Behavior. Arrhenius Definition. Arrhenius Definition Acids Taste sour Burn Skin Turn Litmus Red Dissolve metals Citrus fruit Vitamin C (Ascorbic Acid) Vinegar Battery Acid Bases Taste Bitter Behavior Burn Skin/Feel Slippery Turn Litmus Blue Soap Ammonia

More information

Acid-Base Titrations. Setup for a Typical Titration. Titration 1

Acid-Base Titrations. Setup for a Typical Titration. Titration 1 Titration 1 Acid-Base Titrations Molarities of acidic and basic solutions can be used to convert back and forth between moles of solutes and volumes of their solutions, but how are the molarities of these

More information

CHEM 12 Acids and Bases 3/22/2016

CHEM 12 Acids and Bases 3/22/2016 Acids and Bases Name: Expected background knowledge from acids and bases introductory reading: Definitions (Arrhenius, BL) of an acid and base Definitions of conjugate acid and base pairs Properties of

More information

Notes: Acids and Bases

Notes: Acids and Bases Name Chemistry Pre-AP Notes: Acids and Bases Period I. Describing Acids and Bases A. Properties of Acids taste ph 7 Acids change color of an (e.g. blue litmus paper turns in the presence of an acid) React

More information

Acids and Bases. When an acid loses a proton, the resulting species is its conjugate base. For example, NH 3 + H +

Acids and Bases. When an acid loses a proton, the resulting species is its conjugate base. For example, NH 3 + H + Acids and Bases Definitions An acid is a proton donor, e.g. HCl. For example, consider the reaction between HCl and H 2 O. HCl + H 2 O H 3 O + + Cl - Acid In this reaction, HCl donates a proton to H 2

More information

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Water a polar solvent: dissolves most ionic compounds as well as many molecular compounds Aqueous solution:

More information

TOPIC 11: Acids and Bases

TOPIC 11: Acids and Bases TOPIC 11: Acids and Bases ELECTROLYTES are substances that when dissolves in water conduct electricity. They conduct electricity because they will break apart into Ex. NaCl(s)! Na + (aq) + Cl - (aq), and

More information

QUESTION (2012:3) (a) (i) Complete the table below showing the conjugate acids and bases. CO 3 H 2 O OH HCN CN -

QUESTION (2012:3) (a) (i) Complete the table below showing the conjugate acids and bases. CO 3 H 2 O OH HCN CN - QUESTION (2012:3) (i) Complete the table below showing the conjugate acids and bases. Conjugate acid Conjugate base - HCO 3 2 CO 3 H 2 O OH HCN CN - (ii) HPO 4 2 (aq) Write equations for the reactions

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. A.P. Chemistry Practice Test: Ch. 14, Acids and Bases Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The conjugate base of HSO4 - is A) H2SO4

More information

Worksheet 23 Strong Acid/Strong Base Titrations

Worksheet 23 Strong Acid/Strong Base Titrations Worksheet 2 Strong Acid/Strong Base Titrations A. Initial ph This is always determined based solely on the initial concentration of the acid or base being titrated. Every mole of acid or base will produce

More information

Today. How to solve all acid/base problems (except the ones we ll do next week) Strong Acid Weak Acid Buffer Weak Base Strong Base

Today. How to solve all acid/base problems (except the ones we ll do next week) Strong Acid Weak Acid Buffer Weak Base Strong Base Today How to solve all acid/base problems (except the ones we ll do next week) Strong Acid Weak Acid Buffer Weak Base Strong Base If you re having trouble go step by step 1. Remove the spectator ions (Na

More information

To see how this data can be used, follow the titration of hydrofluoric acid against sodium hydroxide below. HF (aq) + NaOH (aq) H2O (l) + NaF (aq)

To see how this data can be used, follow the titration of hydrofluoric acid against sodium hydroxide below. HF (aq) + NaOH (aq) H2O (l) + NaF (aq) Weak Acid Titration v120413 You are encouraged to carefully read the following sections in Tro (2 nd ed.) to prepare for this experiment: Sec 4.8, pp 158-159 (Acid/Base Titrations), Sec 16.4, pp 729-43

More information

A strong acid and the salt of its conjugate base don't make a good buffer. Why? (aq) + OH - (aq)

A strong acid and the salt of its conjugate base don't make a good buffer. Why? (aq) + OH - (aq) 5.111 Lecture Summary #23 cid/base Equilibrium Continued From Friday s handout Topic: Titrations 23.1 cid buffer action: The weak acid,, transfers protons to O ions supplied by strong base. The conjugate

More information

AP Chemistry Summary Acids, Bases and Buffers Definitions:

AP Chemistry Summary Acids, Bases and Buffers Definitions: AP Chemistry Summary Acids, Bases and Buffers Definitions: Arrhenius: Acid - Produces H + ions in solution HCl H + (aq) + Cl - (aq) Base - Produces OH - ions in solution NaOH Na + (aq) + OH - (aq) Dissociation

More information

Problems you need to KNOW to be successful in the upcoming AP Chemistry exam.

Problems you need to KNOW to be successful in the upcoming AP Chemistry exam. Problems you need to KNOW to be successful in the upcoming AP Chemistry exam. Problem 1 The formula and the molecular weight of an unknown hydrocarbon compound are to be determined by elemental analysis

More information

4C-6 ph of a solution containing 0.75 M lactic acid and 0.25 M sodium lactate. Use the buffer formula: + ] and [OH ] <<.25 and.75.

4C-6 ph of a solution containing 0.75 M lactic acid and 0.25 M sodium lactate. Use the buffer formula: + ] and [OH ] <<.25 and.75. Chem 220 Buffer Problems Exploration C You should memorize the buffer formulas. They look like the K a definition but have added restrictions. K a = [H +]M NaA M HA K a = [H +]M B M BHCl if [H + ] and

More information

When a very strong aqueous acid reacts with a very strong aqueous base, the net reaction occurs between the hydronium and hydroxide ions.

When a very strong aqueous acid reacts with a very strong aqueous base, the net reaction occurs between the hydronium and hydroxide ions. Experiment 2-A ACID-BASE TITRATIONS CHM 1041 The Equivalent Mass of an Unknown Acid EqWt.wpd DISCUSSION Brknsted-Lowry theory defines an acid as a hydrogen ion (H + ) donor and a base as a hydrogen ion

More information

Chem 1B Dr. White 1. Chapter 14 Acids and Bases. 14.1 Nature of Acids and Bases. A. Acids. B. Bases

Chem 1B Dr. White 1. Chapter 14 Acids and Bases. 14.1 Nature of Acids and Bases. A. Acids. B. Bases Chem 1B Dr. White 1 Chapter 14 Acids and Bases 14.1 Nature of Acids and Bases A. Acids B. Bases Chem 1B Dr. White 2 C. Arrhenius Definition 1. acid 2. base 3. Acid-base reaction involving Arrhenius acids

More information

1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436 #1, 7, 8, 11

1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436 #1, 7, 8, 11 SCH3U- R.H.KING ACADEMY SOLUTION & ACID/BASE WORKSHEET Name: The importance of water - MAKING CONNECTION READING 1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436

More information

CHAPTER 9. ANS: a. ANS: d. ANS: c. ANS: a. ANS: c

CHAPTER 9. ANS: a. ANS: d. ANS: c. ANS: a. ANS: c CHAPTER 9 1. Which one of the following is the acid in vinegar? a. acetic acid b. citric acid c. muriatic acid d. ascorbic acid 2. Which is a basic or alkaline substance? a. gastric fluid b. black coffee

More information

Molarity of Ions in Solution

Molarity of Ions in Solution APPENDIX A Molarity of Ions in Solution ften it is necessary to calculate not only the concentration (in molarity) of a compound in aqueous solution but also the concentration of each ion in aqueous solution.

More information

Titration Curve of a Weak Acid

Titration Curve of a Weak Acid Titration Curve of a Weak Acid Amina Khalifa El-Ashmawy, Ph.D. Collin College Department of Chemistry Introduction: Titration is an analytical process whereby two reactant solutions are carefully reacted

More information

PART I: EQUILIBRIUM. 3. Explain why the tetraamminecopper(ii) solution appears blue.

PART I: EQUILIBRIUM. 3. Explain why the tetraamminecopper(ii) solution appears blue. Part A: Formation of a Complex Ion PART I: EQUILIBRIUM Anhydrous copper(ii) sulfate is white, whereas hydrated copper(ii) sulfate is blue. The structure of the hydrated compound is more accurately represented

More information