1. Introduction to Acids, Bases

2. Arrhenius Definition of Acids and Bases
Acids dissociate to produce H+ ions in aqueous (water) solutions
HCl H+ (aq) + Cl- (aq)
Bases dissociate to produce OH- ions in aqueous (water) solutions
NaOH Na+ (aq) + OH-(aq)

3. Dissociation
Dissociation: when a compound splits apart into ions in solution.
How might these dissociate?
H2SO4
KOH
DO NOW:
Packet page 3, #7
Practice Writing Dissociation Equations

4. Note:
Acids and Bases are only reactive if their ions are dissociated (when aqueous)
HCl (l) = hydrogen chloride
HCl (aq) = hydrochloric acid

5. Getting to Know Some Acids

6. Some Common Acids See Table K
HCl hydrochloric acid
HNO3 nitric acid
H3PO4 phosphoric acid
H2SO4 sulfuric acid
HC2H3O2 acetic acid 6

7. The Hydronium Ion (H30+) Acids produce the H+ ion
This is just a “bare proton” and is very reactive.
It immediately forms a coordinate covalent bond with nearby water molecules to form (H30+).
Do Now:
Draw the formation of the Hydronium Ion

8. Organic Acids Contain carbon
Only one of the hydrogens is “acidic” and dissociates in solution
Ex: Acetic Acid
HC2H3O2 or CH3COOH

9. Naming Acids (Honors) Binary Acids Hydro __________ ic Acid
(Contain 2 elements only)
Ex: HCl, HBr, H2S, HF
Hydro __________ ic Acid

10. Naming Acids (Honors) Ternary Acids Look at name of polyatomic ion
(Contain hydrogen and a polyatomic ion)
Do NOT start with “Hydro”
Look at name of polyatomic ion
If it ends in “ate” the acid ends in “ic”
If it ends in “ite” the acid ends in “ous”

11. Name These Acids (Honors)
HBr
HNO3
H3PO4
HNO2
H2C2O4
HClO
HBrO
HClO4
H2S
HIO3

12. Name These Acids (Honors)
HBr = hydrobromic acid
HNO3 = nitric acid
H3PO4 = phosphoric acid
HNO2 = nitrous acid
H2C2O4 = oxalic acid
HClO = hypochlorous acid
HBrO = hypobromous acid
HClO4 = perchloric acid
H2S = hydrosulfuric acid
HIO3 = iodic acid

13. Getting to Know Some Bases

14. Naming Bases All Arrhenius bases contain the hydroxide ion
Name ends in “hydroxide”
Ex: LiOH = lithium hydroxide
Note:
There are “Non” Arrhenius Bases, more on them later

15. Some Common Bases See Table L
NaOH sodium hydroxide
KOH potassium hydroxide
Ba(OH)2 barium hydroxide
Mg(OH)2 magnesium hydroxide
Al(OH)3 aluminum hydroxide 15

16. C2H5OH for example is not a base.
Important Note
There are no “organic bases” (containing carbon).
C2H5OH for example is not a base.
It is an alcohol.
The OH on this molecule does not dissociate to form OH- (hydroxide ion)

17. Salts “Salts” are ionic compounds that are not acids or bases.
Metal cation (+) & nonmetal anion (-)
Ex: NaCl, MgSO4, Li2S

18. Learning Check Acid, Base Name or Salt CaCl2 ______ _______________
KOH ______ _______________
Ba(OH)2 ______ _______________
HBr ______ _______________
H2SO4 ______ ________________ 18

19. Answers Acid,Base Name or Salt CaCl2 salt calcium chloride
KOH base potassium hydroxide
Ba(OH)2 base barium hydroxide
HCl acid hydrochloric acid
H2SO4 acid sulfuric acid

20. Electrolytes Acids & Bases & Salts are electrolytes
Produce free ions when dissolved
Solutions will conduct.
More concentrated = more conductive.
Do Now:
Practice Ditto on Identifying Electrolytes

21. Taste & Feel Acids: taste sour and give a burning sensation if touched
Bases: taste bitter and feel slippery if touched
DO NOT attempt to determine an acid or base by taste or touch ever in the lab!

22. Let’s Review
Which substance, when dissolved in water, forms a solution that conducts an electric current?
(1) C2H5OH    
(3) C12H22O11 (2) C6H12O6    
(4) CH3COOH

23. A solid substance was tested in the
laboratory. The test results are listed below. • dissolves in water • is an electrolyte • melts at a high temperature
Based on these results, the solid substance
could be
(1) Cu              
(3) C
(2) CuBr2         
(4) C6H12O6

24. The compound HNO3 can be described as an
(1) Arrhenius acid and an electrolyte
(2) Arrhenius acid and a nonelectrolyte
(3) Arrhenius base and an electrolyte
(4) Arrhenius base and a nonelectrolyte

25. Based on Reference Table F, which of these salts is the best electrolyte?
A. sodium nitrate
B. magnesium carbonate
C. silver chloride
D. barium sulfate

26. A substance that conducts an electrical current when dissolved in water is called
(1) a catalyst  
       
(2) a non-electrolyte
(3) a metalloid   
    
(4) an electrolyte

27. Which compound is an Arrhenius acid?
(1) CaO 
(2) K2O
(3) HCl  
(4) NH3

28. When one compound dissolves in water, the only positive ion produced in the solution is H3O+(aq). This compound is classified as
(1) a salt
(2) a hydrocarbon
(3) an Arrhenius acid
(4) an Arrhenius base

29. Which substance is an Arrhenius acid?
(1) Ba(OH)2  
        
(2) H3PO4
(3) CH3COOCH3  
(4) NaCl

30. Which compound releases hydroxide ions in an aqueous solution?
(1) CH3COOH  
(2) HCl
(3) CH3OH   
      
(4) KOH

31. An Arrhenius base yields which ion as the only negative ion in an aqueous solution?
(1) hydride ion 
        
(2) hydronium ion
(3) hydrogen ion     
(4) hydroxide ion

32. The compound NaOH(s) dissolves in water to yield
(1) hydroxide ions as the only negative ions
(2) hydroxide ions as the only positive ions
(3) hydronium ions as the only negative ions
(4) hydronium ions as the only positive ions

33. How are HNO3(aq) and CH3COOH(aq) similar?
(1) They are Arrhenius acids and they turn blue litmus red.
(2) They are Arrhenius acids and they turn red litmus blue.
(3) They are Arrhenius bases and they turn blue litmus red.
(4) They are Arrhenius bases and they turn red litmus blue.

34. Acids “Corrode” Certain Metals
See Reference Table J
Metals above Hydrogen on the table will react with acids to form a salt and H2 gas
Single Replacement Reaction
2Zn(s) + 2HCl(aq) ZnCl2(aq) + H2(g)

35. Will an acid react with these metals?
If so complete and balance the single replacement reaction.
Mg + HNO3
Cu + HCl
Ca + H2SO4

36. Answers Mg + 2HNO3 Mg(NO3)2 + H2
Cu + HCl No reaction Cu in below hydrogen on Table J
Ca + H2SO Ca(SO4) + H2

37. Bases DO NOT corrode metals
Interactive:
Acid, Bases and Metals BBC (good for Indicators)
DO NOW:
Packet page 2 and 3, # 4, #5

38. pH Scale Used to help determine how acidic or basic something is.
pH = 7 Neutral
pH < 7 Acidic
pH > 7 Basic

39. Acids & Bases Neutralize Each Other
H+ ion and OH- ions will join together to form neutral water.
Reaction is slightly exothermic (See Table I)
H+ (aq) + OH- (aq) → H2O (l)

40. Determining if it is an Acid or Base
How can you tell if something is acidic or basic?

41. Use an electronic pH meter

42. Use an indicator such as litmus

43. Use pH paper containing universal indicator

44. Acid/Bases Indicators Using Table M
Litmus
pH range for color change
(4.5 – 8.3)
Color change: red to blue
Phenolphthalein
(8 - 9)
Color change: colorless to pink
What color would these be if
pH = 10?
pH = 3?

45. Let’s Review
Based on the results of testing colorless solutions with indicators, which solution is most acidic?
(1) a solution in which bromthymol blue is blue
(2) a solution in which bromcresol green is blue
(3) a solution in which phenolphthalein is pink
(4) a solution in which methyl orange is red

46. According to Reference Table M, what is the color of the indicator methyl orange in a solution that has a pH of 2?
(1) blue 
      
(2) orange
(3) yellow    
(4) red

47. Which indicator would best distinguish between a solution with a pH of 3.5 and a solution with a pH of 5.5?
(1) bromthymol blue 
   
(2) litmus
(3) bromcresol green   
(4) thymol blue

48. Which indicator is blue in a solution that has a pH of 5.6?
(1) bromcresol green 
(2) methyl orange
(3) bromthymol blue  
(4) thymol blue

49. Which indicator is yellow in a solution with a pH of 9.8?
(1) methyl orange
      
(2) bromcresol green
(3) bromthymol blue 
(4) thymol blue

50. In which solution will thymol blue indicator appear blue?
(1) 0.1 M CH3COOH   
(2) 0.1 M HCl
(3) 0.1 M KOH   
         
(4) 0.1 M H2SO4

51. Properties of Acids (Summary)
Produce H+ (as H3O+) ions in water
Electrolytes (conduct in solution)
Taste sour
pH is < 7
Corrode metals (see Table J)
React with bases to form salts and water (Neutralization)

52. Properties of Bases (Summary)
Produce OH- ions in water
Electrolytes (conduct in solution)
Taste bitter, chalky
pH is >7
Feel soapy, slippery
React with acids to form salts and water (Neutralization)

53. Learning Check
Describe the solution in each of the following as: 1) acid 2) base or 3)neutral.
A. ___soda
B. ___soap
C. ___coffee
D. ___ wine
E. ___ water
F. ___ grapefruit 53

54. Solution Describe each solution as: 1) acid 2) base or 3) neutral.
A. _1_ soda
B. _2_ soap
C. _2_ coffee
D. _1_ wine
E. _3_ water
F. _1_ grapefruit 54

55. Learning Check Identify each as characteristic of an
A) acid or B) base
____ 1. Sour taste
____ 2. Produces OH- in aqueous solutions
____ 3. Chalky taste
____ 4. Is an electrolyte
____ 5. Produces H+ in aqueous solutions 55

56. Solution Identify each as a characteristic of an A) acid or B) base
_A_ 1. Sour taste
_B_ 2. Produces OH- in aqueous solutions
_B_ 3. Chalky taste
A, B 4. Is an electrolyte
_A_ 5. Produces H+ in aqueous solutions 56