A buffer is a solution that resists changes in ph upon the addition of a small amount of strong acid or strong base.
|
|
- Tamsin Pierce
- 7 years ago
- Views:
Transcription
1 Chapter 16 Worksheet 1 Buffers and the Henderson-Hasselbalch Equation 1. State the operational and technical definitions of a buffer. Operational definition (What does it do?): A buffer is a solution that resists changes in ph upon the addition of a small amount of strong acid or strong base. Technical definition (How do you make one?): A buffer is composed of a mixture of a weak acid its conjugate base. (Sometimes a solution that is technically a buffer does NOT resist changes in ph. This occurs when so much acid or base are added to the buffer that they become the excess reactant.) 2. The ph of a buffer is determined by two things: The Ka (or pka) of the conjugate acid and [A-] = moles A [HA] moles HA
2 3. Write equations that show what happens when a small amount of strong acid (H+) or strong base (OH-) are added to a buffer. HA + OH- -7 A- + H 2 0 (conjugate acid neutralizes added strong base) A- + H+ -7 HA (conjugate base neutralizes added strong acid) (Note: For a buffer to resist changes in ph, the added OH- or the added H+ must be limiting. If they are not you say that you have exceeded the "buffering capacity".) 4. Explain why the ph does not change very much when a small amount of strong acid or strong base are added to a buffer. The ph does not change very much because (A"] I (HA] does not change very much. This is true as long as the amount of strong acid or base added is small compared to the amount of conjugate acid and conjugate base in the buffer. Ifyou add too much strong acid or base, you will exceed the buffering capacity. 5. What is meant by "buffering capacity"? What determines "buffering capacity"? Buffering capacity refers to the amount of added acid or added base that can be neutralized by a buffer. It is determined by the concentrations of the conjugate acid and conjugate base. Buffering capacity increases as these concentrations increase. 6. Most often (but not always) buffers are prepared such that the concentrations of the conjugate acid and base are similar. Why? So the buffer will have equal capacity to neutralize either added base or added acid. 2
3 . m -:-' : \_ '"" 7. Calculate the ph of the following 3 solutions. a. A M solution ofhf (Ka = 7.1 x 10-4 ) b. A M solution ofnaf (Kb = 7) c. A buffer that contains both M HF and M NaF _ -t-'1 Hf. t t-\ ;;:: ~ \- tt"? 0 ~ ~...,. l )<.ICl _-t,.z -::. l.()((0- u1 O.ls(r'><.., o c ~,L X ~ (tj3 6 "t"j -:::. (, 30)(((l fa. x (~!.l= "P ~7~VV"Q ')(... C.z.S'O U 2.,_~_... ~ _ 1 (-.. v la-it" ((J.2S"C'l -- I ~3)<\6 M..._ \fft-- lb~ cl~se~ b~)~~~~~~--~~~~~--~----~.i!:. =- Vl..K(~""'U (3.z.;-C!---A 'I- ~ l:atl-l -:. i.~i xto_ C M rd~ '" '5".7). r~!-1 ~ '"6. t71 p.",)"y.; -.. C. z.s"(.>-'k -:.. G.1.J sc::. ~-~ ~~~~~~ <-\ T~..-e a~ '3 ~c~ctlc"~>'"\c; V'G-r~"'l) ~re : H F_ ~ tl7- G -Ii! <;: - 4- ~7C + <E: U~~ ~.s (loaq ~ 1::-\- ''; 1"4. "'" l~ c""'> ~ + tl;z..o ~ ~sr -+ 0" - flo.4- c.ylt{ (et+- ~CJU co.icjqt, L f..l:s0-t] i-l t..\. ~ - ~ ~ ~ ~ 0' ~<...+t 'j ~ H~ + l-'-z.o ~ t - + t-t~ot \<''''' -=l.l ')(( O.2SCJ - G F 0 N~\-4?.!< ; H-J~ i () ~ ~ c -Y- +- ~ +-)<. p~lc;l- tl-<;+ Y-. slou\d \7~ 'S!:'1\I~~ -flqil\ I V1 E O.1..s(I~ - G~f')( ')( (J or+ CI\ \ '5G ~ en"" c6's~ G.l.S()-)( --::..Ovz,.s() ~ q;.q. (J. 2..«;0 ~ X ~0-21> Q ~ (O.~ i.. "Cd-X = 7.1-'<..I6-'-t ( <.:2-.93, -'y( \ ( 0:1..)'>0\, X ~ \: f.l,p~] = ~ ""3,"5 /,-~'1 3 lr H~ ~Hr;-\ Gre,,~'- ~'" I'"r\-a, \- l~'> 1kt~ po-r+ 61
4 8. The Henderson-Hasselbalch (H-H) equation provides a recipe for making a buffer of a given ph. It is simply the logarithmic form ofthe Ka expression for the conjugate acid. a. Derive the H-H equation below. When you mix a weak acid with its conjugate base, the acid ionization reaction shifts to the left so the % ionization drops. Thus, we can assume that [HA]eq = [HA]o and [K]eq = [A-]o and no ICE table is required. HA= H+ +A (H +] - K (BA]0 at a [A-]0 -loglln = -logk. -log( ~:) ph = pk. -log( ~:J ph =pk. +Jo{~)) Henderson-Hasselbalch equation If [HA] = [A-] then [H+] = Ka and ph = pka [A-] moles A- ph pka + log -- = pka + log -- [HA] moles HA If [A] = [HA] then ph::;: pka If [A-] > [HA] then ph > pka If [A-] < [HA] then ph < pka 4
5 9. The Ka for HF is 7.1 x 10-4 so its pka a. Mix 10.0 ml of0.500 M HF with 10.0 ml of M NaF. ph =?J.L5" b. Mix 1.00 ml of M HF with 10.0 ml of M NaF. ph 4. (5' c. Mix 10.0 ml of0.500 M HF mixed with 1.00 ml of M NaF. ph = ---=.'2,-,~15",-- [F-] d. A mixture ofhf and NaF has a ph of =--+10-",,-=0 [HF] 10. Use the Henderson-Hasselbalch equation to calculate the ratio ofhc03'to H2C03 in normal blood L pka -loge 4.2 x 10'7) = 6.38 [A -] =10pH,pKa= = = 10.5 [HA] The ratio is so high because blood needs to be able to neutralize more acid than base. That's because cellular metabolism produced acidic waste products that are pumped into the blood. 11. Circle the conjugate acid-base pair that you would choose to prepare a buffer solution that has a ph of a. HCIO and CIO' b. C6HsCOOH and C6HSCOO' c. HPO/' and P0 4, (Ka 3.5 x 10'8) (Ka = 6.3 x ) (Ka 3.6 x 10,13) Explain your choice: Benzoic acid and the benzoate ion is the best choice because the pka of benzoic acid is closest to Therefore, the resulting buffer will have a base to acid ratio close to one. 12. A buffer's job is to prevent large ph changes upon the addition of small amounts of either strong acid or strong base. As long as the buffer capacity is not exceeded, any added strong acid or strong base will be neutralized by the buffer components. Let's look at this process quantitatively. a. What is the ph of a buffer made by mixing 10 ml of OAO M sodium dihyrdogen phosphate with 10 ml of 0.40 M~en phosphate? The 3 Ka values for phosphoric acid are: Kal = 7.5 X 10'3, Ka2 = 6.2 x 10' Ka3 4.8 X 10,13. I. \ (,):1.- -rtr. ~"'" I I.. Qa.i~ b::tse ~? POr t~ ~ Cc.V\ )Vly~ ~ QC lo ) +t \.~ ~s j - ) -~ kc; '<:: K <:l '2 ':; G.. 2'" {O lptl~ 12.(J 5
6 b. Write the net ionic equations for the neutralization reactions that occur upon addition of a small amount ofnaoh (or any metal hydroxide) or HCl (or any strong acid) to the buffer. Add strong base: l-l'l POq- +0 (-e ~ Hpaq2- t t-i'lg Add strong acid: I~ r au,1.- t rt:'jo-\- -"t ~~(7G.t- -{. (-tzj c. What is the ph after 20.0 ml of0.0 10M NaOH or M HCl is added to the buffer?... w.. f3ta'- ~~r lll\l~it;ii) C(,..,t-c.#~(\ ", (O.OlO l ) (C,\.-(6 ""-t).". L{.OXt0 3 f-"<! elf bcjl, ~h.pct!- ~ ~r~l- Ao'Jd,.~ L ). (('J~) U ~) -=. ).0)(..,,0...t..( f'-'<:) ("'.-It """_\ t~r Ol-! - <:.IV- N30 t
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 information3 The Preparation of Buffers at Desired ph
3 The Preparation of Buffers at Desired ph Objectives: To become familiar with operating a ph meter, and to learn how to use the Henderson-Hasselbalch equation to make buffer solutions at a desired ph
More informationChapter 9 Lecture Notes: Acids, Bases and Equilibrium
Chapter 9 Lecture Notes: Acids, Bases and Equilibrium Educational Goals 1. Given a chemical equation, write the law of mass action. 2. Given the equilibrium constant (K eq ) for a reaction, predict whether
More informationChemical 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 informationReview 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 informationTitration 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 informationName 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 informationWorksheet 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 informationWe 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 informationph: 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 informationWrite the acid-base equilibria connecting all components in the aqueous solution. Now list all of the species present.
Chapter 16 Acids and Bases Concept Check 16.1 Chemists in the seventeenth century discovered that the substance that gives red ants their irritating bite is an acid with the formula HCHO 2. They called
More informationSimilarities The ph of each of these solutions is the same; that is, the [H + ] is the same in both beakers (go ahead and count).
Compare 1 L of acetate buffer solution (0.50 mol of acetic acid and 0.50 mol sodium acetate) to 1 L of HCl solution AcO - AcO - H+ Cl - AcO - AcO - Cl - Cl - AcO - Cl - Cl - Cl - Cl - AcO - AcO - AcO -
More informationChem101: General Chemistry Lecture 9 Acids and Bases
: General Chemistry Lecture 9 Acids and Bases I. Introduction A. In chemistry, and particularly biochemistry, water is the most common solvent 1. In studying acids and bases we are going to see that water
More information6) 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 informationNH 3 + H 2 O + OH - NH 4. Acid-Base Concepts -- Chapter 15 + H + Conjugate Acid-Base Pairs: - H + base. acid
Acid-Base Concepts -- Chapter 15 1. Arrhenius Acid-Base Concept (last semester) Acid: H+ supplier Base: OH- supplier 2. Brønsted-Lowry Acid-Base Concept (more general) (a) Definition (H+ transfer) Acid:
More informationCHAPTERS 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 informationChapter 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 informationAcid-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 informationNote: (H 3 O + = hydronium ion = H + = proton) Example: HS - + H 2 O H 3 O + + S 2-
AcidBase Chemistry Arrhenius acid: Substance that dissolves in water and provides H + ions Arrhenius base: Substance that dissolves in water and provides OH ions Examples: HCl H + and Cl Acid NaOH Na +
More informationAcids and Bases: A Brief Review
Acids and : A Brief Review Acids: taste sour and cause dyes to change color. : taste bitter and feel soapy. Arrhenius: acids increase [H ] bases increase [OH ] in solution. Arrhenius: acid base salt water.
More informationQ.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 informationTo 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 informationThis value, called the ionic product of water, Kw, is related to the equilibrium constant of water
HYDROGEN ION CONCENTRATION - ph VALUES AND BUFFER SOLUTIONS 1. INTRODUCTION Water has a small but definite tendency to ionise. H 2 0 H + + OH - If there is nothing but water (pure water) then the concentration
More informationAn acid is a substance that produces H + (H 3 O + ) Ions in aqueous solution. A base is a substance that produces OH - ions in aqueous solution.
Chapter 8 Acids and Bases Definitions Arrhenius definitions: An acid is a substance that produces H + (H 3 O + ) Ions in aqueous solution. A base is a substance that produces OH - ions in aqueous solution.
More informationAnswer Key, Problem Set 5 (With explanations)--complete
Chemistry 122 Mines, Spring 2016 Answer Key, Problem Set 5 (With explanations)complete 1. NT1; 2. NT2; 3. MP; 4. MP (15.38); 5. MP (15.40); 6. MP (15.42); 7. NT3; 8. NT4; 9. MP; 10. NT5; 11. NT6; 12. MP;
More informationp3 Recognizing Acid/Base Properties when p11 Recognizing Basic versus Nonbasic
General Chemistry II Jasperse Acid-Base Chemistry. Extra Practice Problems 1 General Types/Groups of problems: Conceptual Questions. Acids, Bases, and p1 K b and pk b, Base Strength, and using K b or p7-10
More informationChemistry 201. Practical aspects of buffers. NC State University. Lecture 15
Chemistry 201 Lecture 15 Practical aspects of buffers NC State University The everyday ph scale To review what ph means in practice, we consider the ph of everyday substances that we know from experience.
More informationCopyright 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 informationCHAPTER 16: ACIDS AND BASES
CHAPTER 16: ACIDS AND BASES Active Learning: 4, 6, 14; End-of-Chapter Problems: 2-25, 27-58, 66-68, 70, 75-77, 83, 90-91, 93-104 Chapter 15 End-of-Chapter Problems: 69-74, 125, 129, 133 16.1 ACIDS AND
More informationACID-BASE TITRATIONS
ACID-BASE TITRATIONS 1 In this exercise you will use Excel to construct titration curves for a titration between a strong acid and strong base and between a weak acid and strong base. To set up a spreadsheet
More informationQUESTION (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 informationQ.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 informationAcids and Bases. Chapter 16
Acids and Bases Chapter 16 The Arrhenius Model An acid is any substance that produces hydrogen ions, H +, in an aqueous solution. Example: when hydrogen chloride gas is dissolved in water, the following
More informationTopic 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 informationNotes on Unit 4 Acids and Bases
Ionization of Water DEMONSTRATION OF CONDUCTIVITY OF TAP WATER AND DISTILLED WATER Pure distilled water still has a small conductivity. Why? There are a few ions present. Almost all the pure water is H
More informationUNIT (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 informationTitrations. 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 information1. 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 informationTopic 5. Acid and Bases
Topic 5 5-1 Acid and Bases Acid and Bases 5-2 There are a number definitions for aicd and bases, depending on what is convenient to use in a particular situation: Arrhenius and Ostwald: Theory of electrolyte
More informationAuto-ionization of Water
2H 2 O H 3 O + + OH Hydronium ion hydroxide ion Q: But how often does this happen? This is the fundamental concept of all acid-base chemistry In pure water, how much of it is water and how much is ions?
More informationChapter 17. How are acids different from bases? Acid Physical properties. Base. Explaining the difference in properties of acids and bases
Chapter 17 Acids and Bases How are acids different from bases? Acid Physical properties Base Physical properties Tastes sour Tastes bitter Feels slippery or slimy Chemical properties Chemical properties
More informationEquilibria Involving Acids & Bases
Week 9 Equilibria Involving Acids & Bases Acidic and basic solutions Self-ionisation of water Through reaction with itself: The concentration of water in aqueous solutions is virtually constant at about
More informationCHEM 1212 Test II. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
CHEM 1212 Test II MULTIPLE CHOICE. Choose the one alternative that est completes the statement or answers the question. 1) At 1000 K, the equilirium constant for the reaction is K p = 0.013. 2NO (g) +
More informationAcid-Base (Proton-Transfer) Reactions
Acid-Base (Proton-Transfer) Reactions Chapter 17 An example of equilibrium: Acid base chemistry What are acids and bases? Every day descriptions Chemical description of acidic and basic solutions by Arrhenius
More informationAcid-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 informationAcid-Base Chemistry. Brønsted-Lowry Acids & Bases
Acid-Base Chemistry ν There are a couple of ways to define acids and bases ν Brønsted-Lowry acids and bases ν Acid: H + ion donor ν Base: H + ion acceptor ν Lewis acids and bases ν Acid: electron pair
More informationAcid/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 informationSince we will be dealing with aqueous acid and base solution, first we must examine the behavior of water.
Acids and Bases Know the definition of Arrhenius, Bronsted-Lowry, and Lewis acid and base. Autoionization of Water Since we will be dealing with aqueous acid and base solution, first we must examine the
More informationAcid/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 informationSuggested Problems: p. 625-627 #58, 59, 65, 69, 74, 80, 85, 86, 90, 92, 93, 98, 99
Chemistry I Accelerated Study Guideline - Chapter 19 Acids, Bases and Salts ------------------------------------------------------------------------------ By the end of this unit, the skills you should
More informationAcid Base Titrations
Acid Base Titrations Introduction A common question chemists have to answer is how much of something is present in a sample or a product. If the product contains an acid or base, this question is usually
More informationChapter 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 informationExperiment 9: Acids and Bases Adapted from: Chemistry, Experimental Foundations, 4th Ed. Laboratory Manual, by Merrill, Parry & Bassow.
Chem 121 Lab Clark College Experiment 9: Acids and Bases Adapted from: Chemistry, Experimental Foundations, 4th Ed. Laboratory Manual, by Merrill, Parry & Bassow. Content Goals: Increase understanding
More informationChapter 16: Acid-Base and Solubility Equilibria: Reactions in Soil and Water
Chapter 16: Acid-Base and Solubility Equilibria: Reactions in Soil and Water Problems: 16.2-16.86 16.1 ACIDS AND BASES: THE BRØNSTED-LOWRY MODEL PROPERTIES OF ACIDS & BASES Acids produce hydrogen ions,
More informationTutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution.
T-27 Tutorial 4 SOLUTION STOICHIOMETRY Solution stoichiometry calculations involve chemical reactions taking place in solution. Of the various methods of expressing solution concentration the most convenient
More informationChemistry 106 Fall 2007 Exam 3 1. Which one of the following salts will form a neutral solution on dissolving in water?
1. Which one of the following salts will form a neutral solution on dissolving in water? A. NaCN B. NH 4 NO 3 C. NaCl D. KNO 2 E. FeCl 3 2. Which one of the following is a buffer solution? A. 0.10 M KCN
More informationStoichiometry and Aqueous Reactions (Chapter 4)
Stoichiometry and Aqueous Reactions (Chapter 4) Chemical Equations 1. Balancing Chemical Equations (from Chapter 3) Adjust coefficients to get equal numbers of each kind of element on both sides of arrow.
More informationCh 8.5 Solution Concentration Units % (m/m or w/w) = mass of solute x 100 total mass of solution mass of solution = mass solute + mass solvent
1 Ch 8.5 Solution Concentration Units % (m/m or w/w) = mass of solute x 100 total mass of solution mass of solution = mass solute + mass solvent % (v/v) = volume of solute x 100 volume of solution filled
More informationVolumetric Analysis. Lecture 5 Experiment 9 in Beran page 109 Prelab = Page 115
Volumetric Analysis Lecture 5 Experiment 9 in Beran page 109 Prelab = Page 115 Experimental Aims To prepare and standardize (determine concentration) a NaOH solution Using your standardized NaOH calculate
More informationSolubility Product Constant
Solubility Product Constant Page 1 In general, when ionic compounds dissolve in water, they go into solution as ions. When the solution becomes saturated with ions, that is, unable to hold any more, the
More informationChapter 14: Acids and Bases
Ch 14 Page 1 Chapter 14: Acids and Bases Properties of Acids Sour taste React with some metals Turns blue litmus paper red React with bases Some Common Acids HCl, hydrochloric acid H 2 SO 4, sulfuric acid
More informationCHM1 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 informationAcids and Bases HW PSI Chemistry
Acids and Bases HW PSI Chemistry Name 1) According to the Arrhenius concept, an acid is a substance that. A) is capable of donating one or more H + B) causes an increase in the concentration of H + in
More informationChemical Equations. Chemical Equations. Chemical reactions describe processes involving chemical change
Chemical Reactions Chemical Equations Chemical reactions describe processes involving chemical change The chemical change involves rearranging matter Converting one or more pure substances into new pure
More informationProperties of Aqueous Solutions of Acids and Bases. CHAPTER 10 Acids, Bases and Salts. Properties of Aqueous Solutions of Acids and Bases
CAPTER Acids, Bases and Salts Properties of Aqueous Solutions of Acids and Bases Strong and Weak Acids Acids are substances that generate in aqueous solutions. Strong acids ionize 0% in water. That is,
More informationDETERMINATION OF PHOSPHORIC ACID CONTENT IN SOFT DRINKS
DETERMINATION OF PHOSPHORIC ACID CONTENT IN SOFT DRINKS LAB PH 8 From Chemistry with Calculators, Vernier Software & Technology, 2000 INTRODUCTION Phosphoric acid is one of several weak acids that present
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
CHE 1400 - Spring 2015 - Chapter 7 Homework 7 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1)According to Arrhenius, an acid and a base will react
More informationTOPIC 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 informationCHAPTER 18 ACID-BASE EQUILIBRIA
CHAPTER 18 ACID-BASE EQUILIBRIA 18.1 The Arrhenius definition classified substances as being acids or bases by their behavior in the solvent water. 18. All Arrhenius acids contain hydrogen and produce
More informationProperties of Acids and Bases
Lab 22 Properties of Acids and Bases TN Standard 4.2: The student will investigate the characteristics of acids and bases. Have you ever brushed your teeth and then drank a glass of orange juice? What
More informationChapter 10 Acid-Base titrations Problems 1, 2, 5, 7, 13, 16, 18, 21, 25
Chapter 10 AcidBase titrations Problems 1, 2, 5, 7, 13, 16, 18, 21, 25 Up to now we have focused on calculations of ph or concentration at a few distinct points. In this chapter we will talk about titration
More informationChem 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 informationAcids and Bases. Problem Set: Chapter 17 questions 5-7, 9, 11, 13, 18, 43, 67a-d, 71 Chapter 18 questions 5-9, 26, 27a-e, 32
Acids and Bases Problem Set: Chapter 17 questions 5-7, 9, 11, 13, 18, 43, 67a-d, 71 Chapter 18 questions 5-9, 26, 27a-e, 32 Arrhenius Theory of Acids An acid base reaction involves the reaction of hydrogen
More information15. Acid-Base Titration. Discover the concentration of an unknown acid solution using acid-base titration.
S HIFT INTO NEUTRAL 15. Acid-Base Titration Shift into Neutral Student Instruction Sheet Challenge Discover the concentration of an unknown acid solution using acid-base titration. Equipment and Materials
More informationAN INDICATORS PROBLEM 2004, 2001 by David A. Katz. All rights reserved. Permission for academic use, provided the original copyright is included.
AN INDICATORS PROBLEM 2004, 2001 by David A. Katz. All rights reserved. Permission for academic use, provided the original copyright is included. The following problem is a variation of an acid-base indicators
More informationph. 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 information5.111 Principles of Chemical Science
MIT OpenCourseWare http://ocw.mit.edu 5.111 Principles of Chemical Science Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. 5.111 Principles
More informationAcid Base Chemistry. Farmington Public Schools Grade Level: 10 Discipline:Chemistry
Acid Base Chemistry Farmington Public Schools Grade Level: 10 Discipline:Chemistry Author(s) Gary Crisanti Heather Rauf DRAFT: 06/30/06 Farmington Public Schools Table of Contents Unit Summary.3...page(s)
More informationThe Determination of Acid Content in Vinegar
The Determination of Acid Content in Vinegar Reading assignment: Chang, Chemistry 10 th edition, pages 153-156. Goals We will use a titration to determine the concentration of acetic acid in a sample of
More informationORGANIC CHEMISTRY I PRACTICE PROBLEMS FOR BRONSTED-LOWRY ACID-BASE CHEMISTRY
RGANIC CHEMISTRY I PRACTICE PRBLEMS FR BRNSTED-LWRY ACID-BASE CHEMISTRY 1. For each of the species below, identify the most acidic proton and provide the structure of the corresponding conjugate base.
More informationAqueous Ions and Reactions
Aqueous Ions and Reactions (ions, acids, and bases) Demo NaCl(aq) + AgNO 3 (aq) AgCl (s) Two clear and colorless solutions turn to a cloudy white when mixed Demo Special Light bulb in water can test for
More informationChapter 16 Acid-Base Equilibria
Chapter 16 Acid-Base Equilibria Learning goals and key skills: Understand the nature of the hydrated proton, represented as either H + (aq) or H 3 O + (aq) Define and identify Arrhenuis acids and bases.
More informationChapter 11: Acids and Bases
188 Chapter 11: Acids and Bases For our purposes, an acid is a substance that produces hydrogen ion (H + ) when dissolved in water. A base is a substance that produces hydroxide ion (OH - ) when dissolved
More information6 Reactions in Aqueous Solutions
6 Reactions in Aqueous Solutions Water is by far the most common medium in which chemical reactions occur naturally. It is not hard to see this: 70% of our body mass is water and about 70% of the surface
More informationSection IIB Acid Base & Complexation Chemistry & Titrations About 4 lectures
Section IIB Acid Base & Complexation Chemistry & Titrations About 4 lectures Chapter 10 Monoprotic A-B Equilibria Coverage All Sections Problems All except the few involving activity or spreadsheets as
More informationI. ACID-BASE NEUTRALIZATION, TITRATION
LABORATORY 3 I. ACID-BASE NEUTRALIZATION, TITRATION Acid-base neutralization is a process in which acid reacts with base to produce water and salt. The driving force of this reaction is formation of a
More informationCHM 130LL: ph, Buffers, and Indicators
CHM 130LL: ph, Buffers, and Indicators Many substances can be classified as acidic or basic. Acidic substances contain hydrogen ions, H +, while basic substances contain hydroxide ions, OH. The relative
More information5.111 Principles of Chemical Science
MIT OpenCourseWare http://ocw.mit.edu 5.111 Principles of Chemical Science Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. Page 1 of 10 pages
More informationAcid Dissociation Constants and the Titration of a Weak Acid
Acid Dissociation Constants and the Titration of a Weak Acid One of the most important applications of equilibria is the chemistry of acids and bases. The Brønsted-Lowry acid-base theory defines an acid
More informationGeneral 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 informationName: 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 informationAP 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 informationAcids and Bases. An Introduction. David A Katz Department of Chemistry Pima Community College, Tucson, AZ, USA
Acids and Bases An Introduction David A Katz Department of Chemistry Pima Community College, Tucson, AZ, USA Properties of Acids 1. Sour taste (examples: vinegar, citric acid, lemon juice) 2. Turns litmus
More information3/6/2014. Chapter 15. Acids and Bases. Stomach Acid and Heartburn GERD. Curing Heartburn. Common Acids. Properties of Acids. Lecture Presentation
Lecture Presentation Chapter 15 Acids and Bases Sherril Soman Grand Valley State University Stomach Acid and Heartburn The cells that line your stomach produce hydrochloric acid. To kill unwanted bacteria
More informationEquilibrium 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 informationCh 15: Acids and Bases
Ch 15: Acids and Bases A c i d s a n d B a s e s C h 1 5 P a g e 1 Homework: Read Chapter 15 Work out sample/practice exercises in the sections, Bonus problems: 39, 41, 49, 63, 67, 83, 91, 95, 99, 107,
More informationChapter 15 Acids and Bases. Fu-Yin Hsu
Chapter 15 Acids and Bases Fu-Yin Hsu Stomach Acid and Heartburn The cells that line your stomach produce hydrochloric acid. To kill unwanted bacteria To help break down food To activate enzymes that break
More informationBuffer solutions. Division of Radiooncology, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany
Buffer solutions WOLF D. KUHLMANN, M.D. Division of Radiooncology, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany Aqueous buffer solutions and acid-base reactions Buffer solutions have the
More informationTo determine the equivalence points of two titrations from plots of ph versus ml of titrant added.
Titration Curves PURPOSE To determine the equivalence points of two titrations from plots of ph versus ml of titrant added. GOALS 1 To gain experience performing acid-base titrations with a ph meter. 2
More information