Chapter 17 Acid–Base (Proton Transfer) Reactions

Slides:



Advertisements
Similar presentations
Daniel L. Reger Scott R. Goode David W. Ball Chapter 15 Solutions of Acids and Bases.
Advertisements

Acids, Bases, and Salts Chapter 19.
Chapter 16 Acid-Base Equilibria
Acids and Bases Chapter 16 Johannes N. Bronsted Thomas M. Lowry
Brønsted-Lowry definition of an acid: An acid is a proton donor. 721.
Chapter 16 Acids and Bases. When gaseous hydrogen chloride meets gaseous ammonia, a smoke composed of ammonium chloride is formed. HCl(g) + NH 3 (g)
Chapter 16 Acids and Bases Properties Arrhenius Definitions Bronsted-Lowry Definitions.
Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Models of Acids and Bases Arrhenius Concept: Acids produce H + in solution, bases produce.
Acid-Base Equilibria Acids and bases are some of the more commonly encountered chemicals Acids and Bases control composition of blood and cell fluids,
Acid-Base Equilibria Chapter 16. Acids 1.Have a sour taste. e.g., Vinegar, lemons, limes, sour milk 2.Cause litmus to change from blue to red. 4. Acid.
Introduction to Acids and Bases AP Chemistry
Created by C. Ippolito January 2007 Acids, Bases, and Salts Objectives: 1.Distinguish 1.Distinguish among strong, weak, and non electrolytes 2.Compare.
Properties of Acids and Bases Acids taste sour, will change the color of an acid base indicator, and can be strong or weak electrolytes in aqueous solution.
Finding pH. © 2011 Pearson Education, Inc. Chapter 14 – Acids and Bases 4. Which of the following metals does not react with hydrochloric acid? A. Calcium.
ACID AND BASES Definition and properties of Acid: Acid is defined as a substance whose aqueous solution possesses the following characteristic properties:
Acids and Bases Chapter 15. Acids in Industry Sulfuric acid, H 2 SO 4, is the chemical manufactured in greatest quantity in the U.S. Eighty billion pounds.
Chapter 16 Acids and Bases. © 2009, Prentice-Hall, Inc. Some Definitions Arrhenius – An acid is a substance that, when dissolved in water, increases the.
Unit 2 Acids and Bases
Acids-Bases Arrhenius: Acid…. A substance that increases the hydrogen ion, H +, concentration when dissolved in H 2 O. Eg. HCl, H 2 SO 4, HC 2 H 3 O 2.
Acids and Bases Chapter Copyright © by Houghton Mifflin Company. All rights reserved. 16 Concept of Acids and Bases According to the Arrhenius concept.
Acids and Bases. Acids are substances that turn blue litmus red, and usually react with metals such as zinc, releasing hydrogen. Examples: hydrochloric.
Chapter 6 (CIC) and Chapter 16 (CTCS) Read in CTCS Chapter Problems in CTCS: 16.3, 5, 7, 9, 11, 15, 19, 21.
Common household substances that contain acids and bases. Vinegar is a dilute solution of acetic acid. Drain cleaners contain strong bases such as sodium.
Acids-Bases Arrhenius: Acid…. A substance that increases the hydrogen ion, H +, concentration when dissolved in H 2 O. Eg. HCl, H 2 SO 4, HC 2 H 3 O 2.
1 Introduction to Acids and Bases The earliest definition was given by Arrhenius: An acid contains a hydrogen atom and dissolves in water to form a hydrogen.
Acid-Base Equilibria. Acids Bases Sour taste React with active metals to release hydrogen gas Change the color of indicators Bitter taste Feel slippery.
Acid-Base Theories The “Boyz”. Acid and Base Theories2 Arrhenius Theory of Acids Acid: molecular substances that breaks-ups in aqueous solution into H+
Unit 9 Acid-Base Chemistry Chapters 14 & 15. ACIDS & BASES Chapter 14.
Acids and bases.
11111 Chemistry 132 NT A man is rich in proportion to the number of things he can let alone. Henry David Thoreau.
NOTES: 19.1 – Acid-Base Theories
1 Reactions in Aqueous Solutions I. 2 Properties of Aqueous Solutions of Acids & Bases Acidic properties taste sour change the colors of indicators turn.
1 Acids, Bases and PH. 2 Some Properties of Acids þ Produce H + (as H 3 O + ) ions in water (the hydronium ion is a hydrogen ion attached to a water molecule)
Acids: taste sour and cause dyes to change color. Bases: taste bitter and feel soapy. Arrhenius: acids increase [H + ] bases increase [OH - ] in solution.
1 Acids & Bases CHM 1046 Bushra Javed Valencia College.
Acids and Bases Chapter 15. Acids Have a sour taste. Vinegar owes its taste to acetic acid. Citrus fruits contain citric acid. React with certain metals.
ACID-BASE EQUILIBRIUM. Arrhenius Theory  Acids – are solutes that produce hydrogen ions H + in aqueous solutions ex. HCl (aq)  H + (aq) + Cl - (aq)
Chapter 15 Acids and Bases. Copyright © Cengage Learning. All rights reserved.15 | 2 Acid–Base Concepts 1.Arrhenius Concept of Acids and Bases 2.Brønsted–Lowry.
Chapter 19: Acids, Bases, and Salts
Acid-Base Equilibrium According to Arrhenius theory, substances were acids if they contained hydrogen ion (H + ), and bases if they contained hydroxide.
Review: Arrhenius Definition of Acids and Bases Acids produce H + in aqueous (water) solutions Acids produce H + in aqueous (water) solutions water water.
ACID/BASE Theories & Review
Acids and Bases Chapter 14. Properties of Acids Acids: taste sour (citrus fruits & vinegar)taste sour (citrus fruits & vinegar) affect indicators (e.g.
1 Acids and Bases - the Three Definitions 1. The Arrhenius Definition of an Acid 2. Acid strength and pK a 3. K a, pK a, pK b 4. polyprotic acids, pK a1,
ACIDS and BASES Chapter 18. Acids and Bases: An Introduction Acidic solution – contains more hydrogen ions than hydroxide ions. [H + ]>[OH - ] Acidic.
15 Acids and Bases Contents 15-1 The Bronsted-Lowry Definitions 15-2 The Ion Product of Water, Kw 15-3 The pH and Other “p” Scales 15-4 Concentrations.
Chapter 14 Aqueous Equilibria: Acids and
Acids and Bases Chemistry 12. Arrhenius Definition of an Acid An acid has a sour taste (ex: vinegar, citric acid) and when placed in water to become an.
…all you need to “get” for the test… In 20 minutes!
Acids, Bases, and pH Chapters 14/15. 1.Aqueous solutions of acids have a sour taste. 2.Acids change the color of acid-base indicators. 3.Some acids react.
Acids and Bases All you ever wanted to know, and more!
Ch. 15: Acids and Bases Dr. Namphol Sinkaset Chem 201: General Chemistry II.
Acids and Bases. Some Properties of Acids þ Produce H + (as H 3 O + ) ions in water (the hydronium ion is a hydrogen ion attached to a water molecule)
Acids and Bases. Acid Properties Sour taste (citrus fruits) Sour taste (citrus fruits) Conduct electric current Conduct electric current Change the color.
8.4 Acid-Base Theories. Recall: Arrhenius’ TheoryAcids:  Arrhenius theory  Arrhenius theory: Any substance that, when dissolved in water, increases.
Models of Acids and Bases Arrhenius Concept: Acids produce H + in solution, bases produce OH  ion. Brønsted-Lowry: Acids are H + donors, bases are proton.
Chapter 16 Acids and Bases. Characteristics Acids: – Bases: – Change the color of dyes.
Acids and Bases Chapter 14. Brønsted-Lowry Theory Brønsted-Lowry describes reactions of acids as involving the donation of a hydrogen ion (H + ) Brønsted-Lowry.
Acids and Bases Chapter 14 Sections 1-3, 11 Acid – produce Hydrogen ions in aqueous solution Base – produce hydroxide ions in aqueous solution Arrhenius.
ERT 207 ANALYTICAL CHEMISTRY ACIDS AND BASES THEORIES ACID BASE EQUILIBRIA IN WATER pH SCALE 27 Jan 2011 (MISS NOORULNAJWA DIYANA YAACOB) 1.
Acids and Bases Characteristics of Acids Acids (ie HCl, H 2 SO 4, HCH 3 COO):  are ionic compounds in aqueous solution  react with many metals to form.
© Houghton Mifflin Harcourt Publishing Company Acids 1.Aqueous solutions of acids have a sour taste. 2.Acids change the color of acid-base indicators.
Acids Acids: produce H + ions Example: Taste sour Can burn Turn litmus paper red Naming Acids: 1 “hydro-” + Nonmetal element root + “-ic” acid Example:
Acid-Base Theories Prentice-Hall Chapter 19.1 Dr. Yager.
ACIDS AND BASES Chapter 18. Properties of Acids taste SOUR acids change litmus RED their aqueous (water) solutions CONTAIN HYDRONIUM (H 3 O + ) IONS react.
19.1 Acid-Base Theories> 1 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved. Chapter 19 Acids, Bases, and Salts 19.1 Acid-Base.
Ch. 14: Acids and Bases 14.1 Intro to Acids and Bases 14.2 Acid Strength 14.3 pH Scale.
Unit 4: Equilibrium, Acids & Bases Part 2: Acids and Bases
Unit 4: Equilibrium, Acids & Bases Part 2: Acids and Bases
Presentation transcript:

Chapter 17 Acid–Base (Proton Transfer) Reactions

Arrhenius Acid–Base Theory An acid ( HCl) is a substance which produces hydrogen ions in water solution. The properties of an acid is the properties of the hydrogen ions. A base (NaOH) is a substance which produces hydroxide ions in water solution. The properties of a base are the properties of the hydroxide ions. The net reaction between a strong acid and a strong base is :  H+ + OH-  H2O   The Arrhenius concept of acids and base is limited because it applies only to aqueous solutions.

Arrhenius Acid–Base Theory An example of an Arrhenius acid: Gaseous hydrogen chloride dissolved in water: HCl(g) H+(aq) + Cl–(aq) An example of an Arrhenius base: Solid sodium hydroxide dissolved in water: NaOH(s) Na+(aq) + OH–(aq)

Arrhenius Acid–Base Theory Properties of an acid must be due to properties of H+. Properties of a base must be due to properties of OH–. Thus the cause of the sour taste of acids is the H+ ion, the cause of the bitter taste of bases is the OH– ion. Other characteristic properties of acids and bases are also due to the H+ and OH– ions in water solutions.

Arrhenius Acid–Base Theory

Brønsted–Lowry Acid–Base Theory An acid is a proton donor. A base is a proton acceptor. An acid-base reaction is a proton-transfer reaction in which the proton is transferred from the acid to a base with formation of another acid and base.

Brønsted–Lowry Acid–Base Theory The base formed when the acid has donated a proton is called the conjugate base of the acid. Acid A ↔ H+ + Conjugate base of acid A The sign ↔ is used to show that the reaction is reversible. The stronger the acid, the weaker the conjugate base, and the weaker the acid, the stronger the conjugate base.

Brønsted–Lowry Acid–Base Theory An acid base reaction is a proton transfer reaction in which a proton is transferred from a stronger acid to a stronger base with formation of a weaker acid and weaker base. Stronger Acid1+ Stronger Base2↔Weaker Acid2+ Weaker Base1 HNO3 + NH3 ↔ NH4+ + NO3- HCl + CH3COO- ↔ HCH3COO + Cl-

Brønsted–Lowry Acid–Base Theory H3O+ is called hydronium ion. The conjugate base of acid HNO3 is NO3-

Brønsted–Lowry Acid–Base Theory Water which can behave as a base in one case and an acid in another is said to be amphoteric.

Brønsted–Lowry Acid–Base Theory

Conjugate Acid–Base Pairs B + HA HB+ + A– base acid acid base proton proton proton proton remover source source remover Conjugate Acid–Base Pair Two species that transform into each other by gain or loss of a proton, H+. HB+ and B and HA and A– are conjugate acid–base pairs

Conjugate Acid–Base Pairs

Conjugate Acid–Base Pairs

Lewis Acid–Base Theory Lewis Theory of Acids and Bases Acid Electron-pair acceptor. Base Electron-pair donor.

Lewis Acid–Base Theory

Relative Strengths of Acids & Bases

Predicting Acid–Base Reactions

Autoionization of water The Water Equilibrium Autoionization of water

Kw is the water constant or equilibrium constant for water The Water Equilibrium H2O(l) H+(aq) + OH–(aq) Kw = [H+] [OH–] = 1.0 × 10–14 Kw is the water constant or equilibrium constant for water If [H+] = [OH–] = x Kw = [H+] [OH–] = 1.0 × 10–14 = x2 x = = 10–7 moles/liter

The Water Equilibrium For water or water solutions: If [H+] = [OH–] = 10–7 M, the solution is neutral. If [H+] > [OH–], the solution is acidic. If [H+] < [OH–], the solution is basic.

The Water Equilibrium Example: What is the hydrogen ion concentration in a solution of 10–4 M sodium hydroxide in which the hydroxide ion concentration is 10–4 M? Is the solution acidic or basic? Solution: GIVEN: [OH–] = 10–4 M WANTED: [H+] EQUATION: Kw = [H+] [OH–] = 10–14 Since [H+] = 10–10 M< [OH–] = 10–4 M, the solution is basic

pH and pOH By definition pH and pOH are given by pH ≡ -log [H3O+] pOH ≡ -log [OH-]   [H3O+] ≡ antilog(-pH) ≡ 10-pH [OH-] ≡ antilog(-pOH) ≡ 10-pOH

pH and pOH What is the pH of a solution with [H+] = 10–5 M? Solution: pH = – log [H+] = – log 10–5 = 5 What is the [OH–] of a solution with pOH = 6? [OH–] = antilog (–pOH) = antilog (–6) = 10–6 M

pH and pOH Kw = [H+] [OH–] = 1.0 × 10–14 [H+] [OH–] = 1.0 × 10–14 – log ([H+] [OH–]) = – log (1.0 × 10–14) – log ([H+] [OH–]) = 14 – log [H+] + (– log [OH–]) = 14 pH + pOH = 14

pH and pOH

pH and pOH Example: The hydrogen ion concentration of a 10–3 M HCl solution is 10–3 M. What are the pH, pOH, and [OH–] of the solution? Solution: pH = – log [H+] = – log 10–3 = 3 pH + pOH = 14 pOH = 14 – pH = 14 – 3 = 11 [OH–] = antilog (–pOH) = antilog (–11) = 10–11 M

pH and pOH A solution is neutral if [H+] = 10–7 M A solution is acidic if [H+] > 10–7 M A solution is basic if [H+] < 10–7 M Using pH = – log [H+] and pOH = – log [OH–], A solution is neutral if pH = 7 A solution is acidic if pH < 7 A solution is basic if pH > 7

Significant Figures and Logarithms In a logarithm, the digits to the left of the decimal are not counted as significant figures. Counting significant figures in a logarithm begins at the decimal point.

pH and pOH Example: The hydrogen ion concentration of a solution is 2.7 × 10–6 M. What are the pH, pOH, and hydroxide ion concentration? Solution: pH = – log [H+] = – log (2.7 × 10–6) = – log (10–6) – log (2.7) = = 6 – log (2.7) = 5.57 (2 significant figures) pH + pOH = 14.00 pOH = 14.00 – pH = 14.00 – 5.57 = 8.43 [OH–] = antilog(–pOH) = antilog(–8.43) = 10–8.43 M =3.7 × 10–9 M

pH and pOH

pH and pOH

pH and pOH Measurement of pH

Homework 15, 17, 21, 23, 39, 41, 55, 59, 64.