1. Acids, Bases, and Salts Chapter 23

2. Acids and Bases – Section 1 What do you think of when you hear acid? Acids have at least 1 hydrogen atom that can be removed Acid: produces H + in a water solution. H + reacts w/ H 2 O to form H 3 O +  hydronium ion

3. Properties of Acids Taste sour Burns on skin Corrosive – irreparable damage React strongly w/ certain metals and produce H 2 gas React w/ indicators to produce different colors Indicator: organic compound that changes color in an acid or base.

4. Common Acids

5. Bases Ex: baking powder, Mallox and antacids are bases Soaps: clean greasy, fatty substances (bases) Base: produce hydroxide ion,OH -, in H 2 O solution. Also, accepts H + ion.

6. Properties of Bases Opposites of acids Many are crystalline solids Most are ionic compounds Feel slippery and have bitter taste Corrosive and cause severe burns React w/ indicators to produce different colors

7. Common Bases

8. Strengths of Acids and Bases Section 2

9. Strong and Weak Acids Strength depend on how many particles dissociate into ions Strong Acid: nearly all molecules dissociate into ions Ex: HCl, HNO 3, H 2 SO 4

10. Strong and Weak Acids Weak Acids: only small amount dissolves in water Ions do the damage – more ions more damage!! Ex: Acetic Acid and Carbonic Acid

11. Strong and Weak Acids

12. Strong vs. Weak Strong:  All Products All Products Weak:  Some Reactants and Some Products

13. Strong and Weak Bases Most bases are ionic compounds Strong Base: dissociate completely to its ions. Ex: sodium hydroxide, NaOH Weak Base: does NOT dissociate completely. Ex: ammonia, NH 3

14. Dilute and Concentration Dilute: more water than acid Concentrated: more acid than water Can have concentrated weak acid and dilute strong acid

15. Measuring Strength pH: measure of concentration of H + More H + the lower the pH Scale from 0 – 14 7 = neutral, concentration of OH - = concentration of H + Below 7 = acidic, more H + Above 7 = basic, more OH -

16. pH Scale

17. Buffers Def: solutions containing ions that react with additional acids or bases to minimize effects on pH

18. Salts Section 3

19. Neutralization Def: rxn between an acid and a base that takes place in a water solution. 2 rxns occur: HCl(aq) + NaOH(aq) H 3 O + (aq) + OH - (aq)  H 2 O(l) water H 3 O + (aq) + OH - (aq)  H 2 O(l) water Na + (aq) + Cl - (aq)  NaCl(aq)salt Na + (aq) + Cl - (aq)  NaCl(aq)salt

20. Salt Formation Salt: compound formed when (-) ion from acid combines with (+) ion from base Ex: NaCl

21. Acid Base Rxns acid + base  salt + water 2HCl(aq) + Ca(OH) 2 (aq)  CaCl 2 (aq) + 2H 2 O(l)

22. Soaps and Detergents Polar(water) and Nonpolar(grease fat) substances “Like dissolves Like” Polar dissolves Polar, etc. Soaps have both Polar and Nonpolar ends Mix with water and grease Mix with water and grease Hydrocarbon Chain is 12 - 18 carbons Hydrocarbon Chain is 12 - 18 carbons

24. Soap Scum Salts form that are insoluble in water Detergents do NOT make insoluble salts can be used in cold water can be used in cold water