Ch. 15 & 16 - Acids & Bases II. pH (p. 481 - 491) C. Johannesson.

Slides:

Advertisements

Similar presentations

Ch. 19 – Acids & Bases II. pH (p. 644 – 658).

Advertisements

PH (potential of Hydrogen). According to the Bronsted-Lowry theory, both acids and bases are related to the concentration of hydrogen ions. Acids will.

Ch.15: Acid-Base and pH Part 1.

Acids and Bases. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0 

Calculating pH of strong acids and bases. Strong acids or bases are those which dissociate completely. HCl(aq) + H 2 O(l) → H 3 O + (aq) + Cl - (aq) So.

Modern Chemistry Chapter 15 Acid-Base Titration and pH

The Ion Product Constant for Water (Kw)

Strong Acid-Base Calculations

Acid/Base Indicators Substance that changes color in the presence of an acid or a base – Red or Blue Litmus – Phenolphthalein (phth) – Bromothymol blue.

Acid-Base Titration and pH

I. Introduction to Acids & Bases Acids & Bases. A. Properties  electrolytes  turn litmus red  sour taste  react with metals to form H 2 gas  slippery.

pH scale Logarithmic scale expressing the H + concentration, [H + ]. If the pH changes by a factor of 1, the [H + ] changes by a factor of 10. pH =

A C I D - B A S E T I T R A T I O N A N D p H

Unit 8: Acids & Bases PART 2: pH, pOH & pK w. The pH Scale pH is a value chemists use to give a measure of the acidity or alkalinity of a solution. Used.

Hydrogen Ions and Acidity. Hydrogen Ions from Water Water is highly polar – what does that mean? Water particles are in continuous motion If they possess.

I. Introduction to Acids & Bases

Chapter 19 More about ACID-BASES. Self-Ionization of Water Two water molecules produce a hydronium ion & a hydroxide ion by the transfer of a proton.

Characteristics of Acids: Table K  Electrolytes  pH scale: less than 7  Litmus: RED  Phenolphthelein: colorless  Contains a high concentration of.

Acids and Bases II Dr. Ron Rusay Summer 2004 © Copyright 2004 R.J. Rusay.

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)

How is pH defined? The pH of a solution is the negative logarithm of the hydrogen-ion concentration. The pH may be represented mathematically, using the.

14.3 pH Scale 14.4 pH of Strong Acids

Acids and Bases.

I. Introduction to Acids & Bases Acids & Bases. A. Properties  electrolytes  turn litmus red  sour taste  react with metals to form H 2 gas  slippery.

* Name the following acids: * HI * HNO 3 * HCl * Write the formula for the following acids: * Hydrofluoric Acid * Nitrous Acid * Hydrobromic acid.

Acid-Base Titration & pH Objectives 1.Describe the self-ionization of water 2.Define pH and give the pH of a neutral solution at 25 o C 3.Explain.

Acids and Bases II Dr. Ron Rusay Summer 2004 © Copyright 2004 R.J. Rusay.

Pg  Amphoteric substance: can act as an acid or as a base ◦ Water is the most common amphoteric substance  Self-ionization of water: H 2.

Acids and Bases. Three Definitions Arrhenius  acid – produces H + in soln  base – produces OH - in soln Bronsted-Lowry  acid – H + donor  base – H.

C. Johannesson Ch. 18- Acids & Bases II. pH. C. Johannesson A. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0 

Chapter 16 Acid-Base Titration and pH. Aqueous Solutions and the Concept of pH Self-ionization of water – 2 water molecules produce a hydronium ion and.

NOTES: 19.2 – Hydrogen Ions & Acidity (pH and pOH)

C. Johannesson Ch. 15 & 16 - Acids & Bases II. pH (p )

Acids & Bases pH. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0  Kw=ionization constant for H2O.

PH And pOH. Water Water autoionizes H 2 O + H 2 O H 3 O+ + OH- Hydrogen ion concentration determines the acidity of the solution Kc = [H3O+][OH-] ionization.

 pH: The negative of the common logarithm of the hydronium ion concentration [H 3 O + ] ◦ pH stands for the French words pouvoir hydrogene, meaning “hydrogen.

I. Introduction to Acids & Bases Ch. 19 – Acids & Bases.

Aqueous Solutions and the Concept of pH Section 15.1.

Section 16.2 Determining the Acidity of a Solution 1.To understand and determine pH and pOH 2.To learn methods for measuring pH of a solution Objectives.

K w, pH, and pOH. IONIZATION OF WATER Water is capable of reacting with itself in an ionization reaction H 2 O (l) + H 2 O (l) ⇌ H 3 O + (aq) + OH - (aq)

Acids & Bases Lesson 6 Strong Acid-Base Calculations.

Logarithms. The logarithm of a number is the number of times 10 must be multiplied by itself to equal that number.

Acid-Base Titration and pH l Aqueous Solution and the Concept of pH – Hydronium Ions and Hydroxide Ions – The pH Scale – Calculating Involving pH l Determining.

I. Introduction to Acids & Bases Acids & Bases. A. Properties  electrolytes  turn blue litmus red  sour taste  react with metals to form H 2 gas 

Acid-Base Titration and pH 1. What ions are associated with acids? Bases? 2.What mathematical operation is the pH scale based on? 3.What is the pH scale?

PH. Ionization of Water  When compounds dissociate/ionize in an aqueous solution, they produce ions - hydronium (H 3 O + ) and hydroxide (OH - )  These.

The pH Scale Hydronium & Hydroxide Ions (H3O+) (OH–) pH Scale

Calculating pH.

PH of Acids and Bases.

Aim # 5: How do we determine the acidity (or basicity) of a solution?

Ch. 19 Acids & Bases II. pH.

Calculating Concentration

Calculating Acidity.

Acids & Bases II. pH.

Unit 14 – Acid, Bases, & Salts

Unit 13 – Acid, Bases, & Salts

Calculating Concentration

Acid/Base: pH and pOH.

Ch. 15 & 16 - Acids & Bases II. pH (p ) C. Johannesson.

Ch – Acids & Bases II. pH (p. 644 – 658).

Calculating Acidity.

Unit 13 – Acid, Bases, & Salts

Unit 15 – Acid, Bases, & Salts

Unit 13 – Acid, Bases, & Salts

Unit 14 – Acid, Bases, & Salts

Unit 13 – Acid, Bases, & Salts

Ch. 14 & 15 - Acids & Bases II. pH.

Presentation transcript:

Ch. 15 & 16 - Acids & Bases II. pH (p. 481 - 491) C. Johannesson

A. Auto-Ionization of Water Water molecules react with other water molecules to IONIZE (make ions). + - H2O + H2O H3O+ + OH- base acid LPChem:Wz

H2O + H2O H3O+ + OH- A. Ionization of Water “Pure” water contains hydronium and hydroxide ions. Note the equilibrium arrow! Auto-ionization only happens to one out of every quarter-billion molecules, so water doesn’t contain enough ions to be an electrolyte. LPChem:Wz

H2O + H2O H3O+ + OH- Kw = [H3O+][OH-] = 1.0  10-14 A. Ionization of Water H2O + H2O H3O+ + OH- The product of the concentrations of H3O+ and OH- in aqueous solution will always equal the equilibrium constant, Kw. Kw = [H3O+][OH-] = 1.0  10-14 C. Johannesson

HCl is a strong acid, [HCl] = [H3O+] A. Ionization of Water Find the hydroxide ion concentration of 3.0  10-2 M HCl. [H3O+][OH-] = 1.0  10-14 [3.0  10-2][OH-] = 1.0  10-14 [OH-] = 3.3  10-13 M Acidic or basic? HCl is a strong acid, [HCl] = [H3O+] [H3O+] > 1x10-7 Or [H3O+] > [OH-]  acidic Acidic C. Johannesson

Write answers in Scientific Notation! A. Ionization of Water Find the hydronium ion concentration of 2.5  10-5 M NaOH. [H3O+][OH-] = 1.0  10-14 [H3O+][2.5  10-5]= 1.0  10-14 [H3O+] = 4.0  10-10 M Acidic or basic? NaOH is a strong base, [NaOH] = [OH-] Write answers in Scientific Notation! Basic [H3O+] < 1x10-7 Or , [H3O+] < [OH-] C. Johannesson

pouvoir hydrogène (Fr.) B. pH Scale 14 7 INCREASING ACIDITY INCREASING BASICITY NEUTRAL pH = -log[H3O+] pouvoir hydrogène (Fr.) “hydrogen power” C. Johannesson

pH of Common Substances B. pH Scale pH of Common Substances C. Johannesson

pH = -log[H3O+] pOH = -log[OH-] pH + pOH = 14 B. pH Scale pH = -log[H3O+] pOH = -log[OH-] pH + pOH = 14 C. Johannesson

B. pH Calculations [H+] pH [OH-] pOH -log[H3O+] 10^(–pH) 14 = pH + pOH Kw = [H3O+][OH-] 14 = pH + pOH -log[OH-] [OH-] pOH 10^(–pOH) LPChem:Wz

B. pH Scale What is the pH of 0.050 M HNO3? pH = -log[H3O+] strong acid  [HNO3] = [H3O+] pH = -log[H3O+] pH = -log[0.050] pH = 1.30 Acidic or basic? __  2 sig figs __  2 sig figs after the decimal Acidic pH < 7 C. Johannesson

B. pH Scale What is the pH of a 1x10-9 M HNO3 solution? Basic HNO3 is a strong acid Therefore [HNO3] = [H3O+] pH = -log[H3O+] pH = -log[1x10-9] = 9.0 Basic LPChem:Wz

B. pH Scale What is the [H3O+] of a solution with pH = 7.45? pH = -log[H3O+] Therefore 10^ -pH = [H3O+] 10^ -7.45 = [H3O+] = 3.6 x 10-8 M LPChem:Wz

B. pH Scale What is the molarity of HBr in a solution that has a pOH of 9.6? Given: Find: HBr is a: [HBr] = pOH Molarity of HBr Strong Acid [H3O+] How do we solve from pOH to [H3O+] ? C. Johannesson

B. pH Calculations [H+] pH [OH-] pOH -log[H3O+] 10^(–pH) 14 = pH + pOH Kw = [H3O+][OH-] 14 = pH + pOH -log[OH-] [OH-] pOH 10^(–pOH) LPChem:Wz

B. pH Scale 10^ -pH = [H3O+] 10^ -4.4 = [H3O+] What is the molarity of HBr in a solution that has a pOH of 9.6? pH + pOH = 14 pH + 9.6 = 14 pH = 4.4 pH = -log[H3O+] or 10^ -pH = [H3O+] 10^ -4.4 = [H3O+] = 4.0  10-5 M HBr Acidic C. Johannesson

B. pH Scale What is the OH- concentration of a solution whose pH is 1.94? Given: Find: pH [OH-] How do we solve from pH to [OH-] ? C. Johannesson

B. pH Calculations [H+] pH [OH-] pOH -log[H3O+] 10^(–pH) 14 = pH + pOH Kw = [H3O+][OH-] 14 = pH + pOH -log[OH-] [OH-] pOH 10^(–pOH) LPChem:Wz

B. pH Scale 10^ -pOH = [OH-] 10^ -12.06 = [OH-] What is the OH- concentration of a solution whose pH is 1.94? pH + pOH = 14 1.94 + pOH = 14 pOH = 12.06 pOH = -log[OH-] or 10^ -pOH = [OH-] 10^ -12.06 = [OH-] = 8.7  10-13 M OH- Acidic LPChem:Wz

B. pH Scale What is the pH of a 0.055 M KOH solution? Given: [OH-] Find: [OH-] pH How do we solve from [OH-] to pH? C. Johannesson

B. pH Calculations [H+] pH [OH-] pOH -log[H3O+] 10^(–pH) 14 = pH + pOH Kw = [H3O+][OH-] 14 = pH + pOH -log[OH-] [OH-] pOH 10^(–pOH) LPChem:Wz

B. pH Scale pH + pOH = 14 What is the pH of a 0.055 M KOH solution? KOH is a strong base Therefore [KOH] = [OH-] pOH = -log[OH-] pOH = -log[0.055] pOH = 1.26 pH + pOH = 14 pH + 1.26 = 14 pH = 12.74 Basic LPChem:Wz