1. Acids and Bases

2. Describing Acids and Bases A. Acids and Bases Acid-contain at least one hydrogen atom Acid-contain at least one hydrogen atom examples: HCl, H 2 SO 4, HNO 3 -the hydrogen atoms can be removed when dissolved in water to form hydrogen ions (H + ) and/or hydronium ions (H 3 O + ) -the hydrogen atoms can be removed when dissolved in water to form hydrogen ions (H + ) and/or hydronium ions (H 3 O + )

3. B. Properties of acids taste sour taste sour feel like water, except on broken skin feel like water, except on broken skin corrosive and can damage skin or tissue corrosive and can damage skin or tissue react with an indicator such as litmus paper react with an indicator such as litmus paper or pH paper to produce a predictable color change - turns blue litmus paper red react with metals to produce hydrogen gas react with metals to produce hydrogen gas dissolves in water to form an electrolyte solution dissolves in water to form an electrolyte solution

4. C. Common Acids 1. Foods contain acids. 1. Foods contain acids. a. Citrus fruits have citric acids. a. Citrus fruits have citric acids. b. Yogurt and buttermilk have lactic acid. b. Yogurt and buttermilk have lactic acid. c. Vinegar, or acetic acid, is in pickled foods. c. Vinegar, or acetic acid, is in pickled foods. 2. The stomach uses hydrochloric acid. 2. The stomach uses hydrochloric acid.

5. 3. Four acids are vital to industry. a. Sulfuric acid is used in car batteries and the manufacturing of fertilizers. manufacturing of fertilizers. b. Phosphoric acid used to manufacture b. Phosphoric acid used to manufacture detergents, fertilizers, and soft drinks detergents, fertilizers, and soft drinks c. Nitric acid is used to manufacture fertilizers c. Nitric acid is used to manufacture fertilizers and explosives. and explosives. d. Steel can be cleaned with hydrochloric acid.

6. D. Base- a substance that forms hydroxide ions (OH - ) in a water solution E. Properties of bases many are crystalline solids in pure undissolved state many are crystalline solids in pure undissolved state taste bitter taste bitter feel slippery in solution feel slippery in solution strong bases are corrosive strong bases are corrosive react with indicators to produce predictable react with indicators to produce predictable color changes, red litmus paper turns blue dissolves in water to form an electrolyte dissolves in water to form an electrolytesolution

7. F. Common bases are used in cleaning products, medications, fabrics, and deodorants. G. Definitions of Acids and Bases Arrhenius Acid-substance that contains hydrogen and ionizes to produce hydrogen ions in an aqueous solution. HCl(g)  H + (aq) + Cl - (aq) Arrhenius Base-a substance that contains a hydroxide group and dissociates to produce a hydroxide ion in an aqueous solution. NaOH(s)  Na + (aq) + OH - (aq)

8. Br  nsted-Lowry Acid-substance that donates a hydrogen ion HF + H 2 O  H 3 O + + F - Br  nsted-Lowry Base-substance that accepts a hydrogen ion NH 3 + H 2 O  NH 4 + + OH - Amphoteric-a substance that can act as both an Amphoteric-a substance that can act as both an acid and a base.

9. Strengths of Acids and Bases A. The strength of an acid or base depends on how completely a compound separates into ions when dissolved in water. 1. A strong acid ionizes almost completely in solution. 2. A weak acid only partly ionizes in solution. 3. A strong base dissociates completely in solution. 4. A weak base does not ionize completely in solution.

10. 5. Strong acids and bases conduct more electricity than weak ones. 5. Strong acids and bases conduct more electricity than weak ones. 6. Equations for strong acids and bases use a single arrow, indicating ions are formed. single arrow, indicating ions are formed. HCl + H 2 O  H 3 O + + Cl - NaOH  Na + + OH - 7. Equations for weak acids and bases use double arrows, pointing in opposite directions, indicating an incomplete reaction. double arrows, pointing in opposite directions, indicating an incomplete reaction. Ca(OH) 2 Ca 2+ + 2OH - HC 2 H 3 O 2 + H 2 O H 3 O + + C 2 H 3 O 2 -            

11. B. Dilute and concentrated are terms used to describe the amount of acid or base dissolved. a. Dilute-few molecules of an acid or base a. Dilute-few molecules of an acid or base dissolved in a volume of solution. dissolved in a volume of solution. b. Concentrated-many molecules of an acid b. Concentrated-many molecules of an acid or base dissolved in a volume of solution. or base dissolved in a volume of solution.

12. What is pH? A. pH-a scale used to classify acids and bases the pH scale ranges from 0-14the pH scale ranges from 0-14 acids have a pH below 7acids have a pH below 7 bases have a pH above 7bases have a pH above 7 neutral substances have a pH of 7neutral substances have a pH of 7

13. B. Ions in solution Acidic solutions have more hydrogen ions than hydroxide ions. Acidic solutions have more hydrogen ions than hydroxide ions. Basic solutions have more hydroxide ions than hydrogen ions. Basic solutions have more hydroxide ions than hydrogen ions. Neutral solutions have an equal number of hydrogen ions and hydroxide ions. Neutral solutions have an equal number of hydrogen ions and hydroxide ions.

14. C. How pH is calculated pH is the negative logarithm of the hydrogen ion concentration pH = - log [H + ] Calculate the pH of a solution having a hydrogen ion concentration of 1.0 x 10 -2 M. pH = - log [H + ] pH = - log[1.0 x 10 -2 ] pH = 2.00

15. D. Using pOH pOH-the negative logarithm of the hydroxide ion concentration. pOH-the negative logarithm of the hydroxide ion concentration. pOH = -log[OH - ] Calculate the pOH of a solution with a hydroxide ion concentration of 1.0 x 10 -6 M. Calculate the pOH of a solution with a hydroxide ion concentration of 1.0 x 10 -6 M. pOH = -log[OH - ] pOH = -log[1.0 x 10 -6 ] pOH = 6.00

16. E. The relationship between pH and pOH pH + pOH = 14 pH = 14 – pOH pOH = 14 – pH

17. Calculate the pH and pOH of the a solution with a hydroxide ion concentration of 3.2 x 10 -9 M. pOH = -log[OH - ] pOH = -log[3.2 x 10 -9 ] pOH = 8.49 pH = 14 – pOH pH = 14 – 8.49 pH = 5.51

18. Neutralization A. Neutralization-chemical reaction between an acid and a base in an aqueous solution producing a salt and water. neutralization is a double replacement reaction. neutralization is a double replacement reaction. B. Salt-ionic compound made up of a cation from a base and an anion from an acid. Mg(OH) 2 + 2HCl  MgCl 2 + 2H 2 O

19. C. Titration is used to determine the concentration of an acidic or basic solution 1. A solution of known concentration is the standard solution. 2. An acid/base indicator is added to the unknown solution. 3. A color change that persists is the end point.