Acids, Bases, and Salts Chapter 19.1 Inquiry Lab Leah sure is sick. The doctor said she can not eat anything acidic. It will make her stomach hurt really bad. How can she tell if she should eat a certain food or not based on its acidity? Ideas?? The Basics Acids: Acids taste sour, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. Bases : Bases taste bitter, feel slippery, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. Examples Citrus fruits contain citric acid. Tea contains tannic acid. Antacids use bases to neutralize excess stomach acid. The base calcium hydroxide is a component of mortar. Types of Acids and Bases 1) Arrhenius Acids and Bases 2) Bronsted-Lowry Acids and Bases 3) Lewis Acids and Bases All three have a different definition for acids and bases, yet all are VALID. Arrhenius Acids Arrhenius said that acids are hydrogen-containing compounds that ionize to yield hydrogen ions (H + ) in aqueous solution. Hydrochloric Acid Common Acids Monoprotic acids: Acids that contain one ionizable hydrogen, such as nitric acid (HNO 3 ) Diprotic acids: Acids that contain two ionizable hydrogens, such as sulfuric acid (H 2 SO 4 ) Triprotic acids: Acids that contain three ionizable hydrogens, such as phosphoric acid (H 3 PO 4 ) Arrhenius Bases He also said that bases are compounds that ionize to yield hydroxide ions (OH ) in aqueous solution. Common Bases Bronsted-Lowry Acids The Brnsted-Lowry theory defines: Bronsted-Lowry Acid: hydrogen-ion donor Bronsted-Lowry Base: hydrogen-ion acceptor Bronsted-Lowry Acids Why is ammonia a base and water an acid? Bronsted-Lowry Conjugate acids and bases: A conjugate acid is the particle formed when a base gains a hydrogen ion. A conjugate base is the particle that remains when an acid has donated a hydrogen ion. Bronsted-Lowry A conjugate acid-base pair consists of two substances related by the loss or gain of a single hydrogen ion. Bronsted-Lowry A substance that can act as both an acid and a base is said to be amphoteric. Water is amphoteric. Sometimes it behaves like a base, and sometimes it behaves like an acid in terms of Bronsted-Lowry Lewis Acids and Bases Lewis acid: accepts a pair of electrons to form a covalent bond. Lewis base: donates a pair of electrons to form a covalent bond. Summary WRITE ME DOWN! Practice Assignment 1) Write chemical equations for: The ionization of HNO 3 in water The reaction of CO 3 -2 in water For each, identify the Bronsted-Lowry acid and base and label the conjugate acid and base pairs. 2) Identify the follow acids as monoprotic, diprotic, or triprotic. Explain your reasoning. H 2 CO 3 H 3 PO 4 HCl H 2 SO 4 Assignment On a piece of paper, summarize your notes by creating a diagram that organizes all three types of acids. Include: Definitions Examples of Acids and Bases in Each Type Any other pertinent information associated with each type Page 625 #45, 46, 48, 49