Chapter 25 Acids, Bases, and Salts

1. Chapter 25 Acids, Bases, and Salts Section 1-Acids and Bases

2. An acid is a substance that produces hydrogen ions in a water solution. • The ability to produce ions is what gives their characteristic properties. • When an acid dissolves in water, H⁺ ions interact with water molecules to form H₃0⁺ ions, which are called hydronium ions. Properties of Acids

3. Citric Acid is found in citrus fruits. • Lactic Acid is found in yogurt and buttermilk. • Vinegar is also known as acetic acid. • Your stomach uses hydrochloric acid to help you digest your food. Common Acids

4. Common Acids

5. A substance that forms hydroxide ions, OH⁻, in a water solution is a base. • A base is also any solution that accepts H⁺ from acids. • Think of bases as the opposite of acids. Properties of Bases

6. In pure and undissolved state many bases are crystalline solids. • In a solution bases feel slippery and have a bitter taste. • Strong bases are like strong acids as they are corrosive and can burn the skin. Properties of Bases

7. Common Bases

8. Ammonia is a popular household cleaner. • Never combine products containing ammonia with other cleaners that contain chlorine such as toilet bowl cleaners and bleach. The reaction produces poisonous gases. • Solutions of both acids and based produce some ions that are capable of carrying electric current to some extent. They are considered to be conductors. Acids & Bases

9. Chapter 25Acids, Bases, and Salts Section 2- Strengths of Acids and Bases

10. The strength of an acid or base depends on how completely a compound separates into ions when dissolved in water. • An Acid that ionizes almost completely in solution is a Strong Acid. ex. Hydrochloric Acid • A weak acid is an acid that only partly ionizes in a solution. Ex. Acetic and Carbonic Acids Strong Acids and Weak Bases

11. The pH of a solution is a measure of the concentration of H⁺ ions in it. • The greater the H⁺ concentration is, the lower the pH is and the more acidic the solution is. • The pH measures how acid or basic a solution is. pH

12. To indicate pH, a scale ranging from 0 to 14 has been devised. pH

13. Solutions with a pH lower than 7 are described as acidic. • Solutions with a pH greater than 7 are described as basic. • A pH of exactly 7 indicates that the concentration of H⁺ ions and OH⁻ ions are equal. These solutions are neutral. Ex. Pure water at 25 degrees has a pH of 7. pH

14. One way to determine pH is by using pH indicator strips. The final color of the pH paper is matched with colors on a chart to find the pH. pH

15. The blood that circulates through your body has a pH of between 7.0 and 7.8 • Your body can not work outside of this pH range. • Does your Blood pH change when you eat spicy/acidic foods? Blood pH

16. You would think that your pH in your blood changes when you eat spicy/acidic foods but it does not. • Your blood contains compounds called Buffers that enable small amounts of acids or bases to absorbed. • Buffers are solution containing ions that react with additional acids or bases to minimize their effects on pH. Blood pH

17. Chapter 25Acids, Bases, and Salts Section 3-Salts

18. Neutralization is a chemical reaction between an acid and a base that takes place in a water solution. • Antacid Tablets are an example of a product that a person suffering from indigestion cant take to “neutralize” the effects of acid reflux. Neutralization

19. A salt is a compound formed when the negative ions from an acid combine with the positive ions from a base.

20. If you need to know the concentration of an acid or base in a solution you can determine it through a process called titration. Titration