Hydrogen Ions and Acidity

Transcription

1 To test a diagnosis of diabetic coma, a doctor orders several tests, including the acidity of the patient s blood. Results from this test will be expressed in units of ph. You will learn how the ph scale is used to indicate the acidity of a solution and why the ph scale is used. 1 of 50 Hydrogen Ions from Water Hydrogen Ions from Water The reaction in which water molecules produce ions is called the self-ionization of water. 2 of 50 1

2 Hydrogen Ions from Water In the self-ionization of water, a proton (hydrogen ion) transfers from one water molecule to another water molecule. 3 of 50 Ion Product Constant for Water Ion Product Constant for Water How are [H + ] and [OH - ] related in an aqueous solution? 4 of 50 2

3 Ion Product Constant for Water For aqueous solutions, the product of the hydrogen-ion concentration and the hydroxide-ion concentration equals Any aqueous solution in which [H + ] and [OH - ] are equal is described as a neutral solution. 5 of 50 Ion Product Constant for Water The product of the concentrations of the hydrogen ions and hydroxide ions in water is called the ion-product constant for water (K w ). 6 of 50 3

4 Ion Product Constant for Water An acidic solution is one in which [H + ] is greater than [OH - ]. 7 of 50 Ion Product Constant for Water Unrefined hydrochloric acid, commonly called muriatic acid, is used to clean stone buildings and swimming pools. 8 of 50 4

5 Ion Product Constant for Water A basic solution is one in which [H + ] is less than [OH ]. Basic solutions are also known as alkaline solutions. 9 of 50 Ion Product Constant for Water Sodium hydroxide, or lye, is commonly used as a drain cleaner. 10 of 50 5

6 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 6

7 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 7

8 Practice Problems for Sample Problem 19.1 Problem Solving Solve Problem 10 with the help of an interactive guided tutorial. 15 of 50 The ph Concept The ph Concept How is the hydrogen-ion concentration used to classify a solution as neutral, acidic, or basic? 16 of 50 8

9 The ph Concept The ph of a solution is the negative logarithm of the hydrogen-ion concentration. 17 of 50 The ph Concept Calculating ph 18 of 50 9

10 The ph Concept A solution in which [H + ] is greater than M has a ph less than 7.0 and is acidic. The ph of pure water or a neutral aqueous solution is 7.0. A solution with a ph greater than 7 is basic and has a [H + ] of less than M. 19 of 50 The ph Concept 20 of 50 10

11 The ph Concept 21 of 50 The ph Concept Calculating poh 22 of 50 11

12 The ph Concept ph and Significant Figures 23 of 50 SAMPLE PROBLEM 24 of 50 12

13 SAMPLE PROBLEM 25 of 50 SAMPLE PROBLEM 26 of 50 13

14 SAMPLE PROBLEM 27 of 50 Practice Problems for Sample Problem Problem Solving Solve Problem 12 with the help of an interactive guided tutorial. 28 of 50 14

15 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 15

16 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 16

17 Practice Problems for Sample Problem 19.3 Problem Solving Solve Problem 14 with the help of an interactive guided tutorial. 33 of 50 Measuring ph Measuring ph What is the most important characteristic of an acid-base indicator? 34 of 50 17

18 Measuring ph An indicator is a valuable tool for measuring ph because its acid form and base form have different colors in solution. 35 of 50 Measuring ph Phenolphthalein changes from colorless to pink at ph of 50 18

19 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 19

20 SAMPLE PROBLEM of 50 SAMPLE PROBLEM of 50 20

21 Practice Problems for Sample Problem 19.4 Problem Solving Solve Problem 15 with the help of an interactive guided tutorial. 41 of 50 Measuring ph Acid-Base Indicators 42 of 50 21

22 Measuring ph 43 of 50 Measuring ph Universal Indicators 44 of 50 22

23 Measuring ph ph Meters 45 of 50 23