Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Chapter 23 Acids, Bases, and Salts Have you seen these? Section 1: Acids & Bases Acid - (H+) removed in H2O. Properties of Acids 1. 2. 3. Taste sour Corrosive and can burn skin React with litmus paper: red to yellow. Common Acids Foods contains acids a. Citrus fruits citric acid b. Vinegar, or acetic acid, is in pickled foods 2. You have hydrochloric acid (HCl) in your stomach. 1. Common Acids 3. Four acids vital to industry. a. b. c. d. Sulfuric acid - used in car batteries and the manufacturing of fertilizers Phosphoric acid - used to manufacture detergents, fertilizers, and soft drinks Nitric acid - used to manufacture fertilizers and explosive Hydrochloric acid – used to clean steel Bases Base - forms hydroxide ions (OH-) in water. Compliments or opposites of acids Properties of Bases 1. 2. 3. 4. Many are crystals Feel slippery Strong bases are corrosive litmus paper turns blue-purple Common Bases 1. 2. 3. Ammonia & Sodium Hydroxide - are used in cleaners, fertilizers, rayon, nylon Magnesium Hydroxide - medications Aluminum Hydroxide – color fast fabrics Solutions of Acids and Bases 1. 2. 3. Acid describes compounds that can be ionized in water to form hydronium ions Base describes compounds that can form hydroxide ions in solution Solutions of acids and solutions of bases are electric conductors to some extent Discussion Questions 1. Why should a person never use taste testing to identify an acid or a base? Answers Acids and Bases can be corrosive and cause damage to tissue Sulfuric, phosphoric, nitric, hydrochloric Section 2 Strength of Acids and Bases The strength of an acid or a base depends on how completely a compound separates into ions when dissolving in water Strong Acids and Strong Bases 1. 2. 3. 1. A strong acid ionizes (or loses H+) almost completely in solution A strong base dissociates (or forms OH-) completely in solution Equations for strong acids and bases use a single arrow indicating ions are formed Strong acids and bases conduct more electricity than weak ones Weak Acids and Weak Bases 1. 2. 4. A weak acid/base only partly ionizes in solution Equations for weak acids and bases use double arrows pointing in opposite directions, indicating an incomplete reaction Dilute and concentrated are terms to describe the amount of acid or base dissolved pH of a Solution 1. pH - a measure of the concentration of hydrogen ions (H+) in a solution or how acidic or basic it is a. b. c. pH lower than 7 = acidic pH greater than 7 = basic pH exactly equal to 7 = neutral pH of a Solution 1. 2. pH is determined by a universal indicator paper or pH meter Buffers – solutions containing ions that react with additional acids or bases to minimize their effects on pH. Discussion Question Is a strong acid the same thing as a concentrated acid? Why or Why Not? Answer Not necessarily the same; strength refers to ionization in a solution while concentration refers to the amount of acid or base dissolved Section 3 Salts Neutralization Chemical reaction between an acid and a base taking place in a water solution Hydronium ions from the acid combine with hydroxide ions from the base to produce neutral water Salts 1. 2. 3. Salt - compound formed when the negative ions from an acid combine with the positive ions of a base Salt is essential for many animals Other salt uses include manufacturing of paint, rubber, glass, soap, detergents, and dry cell batteries Titration Used to determine the concentrations of an acidic or basic solution 2. A solution of known concentration is the standard solution 3. An acid/base indicator is added to an unknown solution 4. A color change that is constant is the end point. 1. Soaps and Detergents Soaps 1. Are organic salts with polar and nonpolar ends. 2. The nonpolar, hydrocarbon end interacts with oil and dirt 3. The polar end helps oil and dirt dissolve in water Detergents 1. Form more soluble salts with the ions in hard water Esters 1. 2. 3. Come from alcohols that are not bases but have a hydroxyl (-OH) group Esters are used in fruit flavorings and perfumes Polyesters are synthetic fibers used to make fabrics Discussion Question What are two ways salts can form? Answer 1. 2. When an acid and a base combine their negative and positive ions When an acid reacts with a metal