1. Chapter 3: Activity 2 Choice of Media for Durability
What do you see?

2. What are acids and bases?

3. Acids Always contain H+ (ex. HCl, H2SO4)
Acidic foods have a sour taste
Neutralize bases
React with most metals
Turns blue litmus red
Have a pH <7
Turns universal indicator yellow, orange, or red

4. Bases Contain OH- (ex. NaOH, KOH) Have a bitter taste Feel slippery
Neutralize acids
Are corrosive
Have a pH >7
Turn red litmus blue
Turn universal indicator green, blue, or purple

5. Acids vs Bases

6. Acids vs Bases

7. Universal Indicator ScalepH
Is a measure of how much H+ is in a solution sample.
If H+= OH- then, pH=7 and the solution is neutral.
If H+ > OH-, then pH<7 and the solution is acidic.
If OH- >H+, then pH>7 and the solution is basic.
The pH scale goes from 0-14, with 7 being neutral
Universal Indicator Scale

8. Take a look at this!!!!!

9. How is pH important to artwork?
What has happened here?

10. How Does This Happen? SO2(g) + H2O(l)  H2SO3(aq) sulfurous acid
sulfuric acid
NO3(g) + H2O(l)  HNO3(aq)
nitric acid

11. Conoco Philips Plant, Linden NJ

12. Conoco Philips Plant, Linden NJ

13. What does acid rain do? CaCO3(s) + H2SO4(aq) CaSO4(aq) + H2O(l) + CO2
Marble sulfuric acid calcium sulfate water carbon dioxide
Dissolves in the water and washes away
Zn (s) + H2SO4(aq)  ZnSO4(aq) + H2(g)
zinc metal sulfuric acid zinc sulfate hydrogen gas
Zinc is usually a good metal choice for outdoor stuff, but in the presence of acid rain, it reacts and washes away.

14. In 1992, after being displayed outdoors in an urban-industrial environment for over 60 years, Philadelphia’s version of Rodin’s The Thinker showed the effects of "acid rain" and particulate deposition common in such atmospheres. Streaking, caused by the run-off of condensate from the sculptural forms, had etched a pattern of irregular rivulets in the surface, while urban aerosols from industrial and vehicular sources built up black and other accretions. The forms were obscured; Rodin’s modeling could no longer be "read," with some high points black and recesses bright due to corrosion.
Philadelphia Museum of Art

15. What might be a better choice of material for outdoor art?
SiO2(s) + H2SO4(aq)  no reaction
Sandstone and granite sulfuric acid

16. How would a protective coating have affected this famous piece of art?
Other alternatives???
The copper in this piece of artwork wouldn’t stand a chance exposed to air and water, BUT a protective coating over it can keep it looking new for ages!
How would a protective coating have affected this famous piece of art?

22. Ted Talk

25. H+ ions or H3O+ ions (hydronium)
Acids
Both
Bases
Sour taste
Bitter taste
pH <7
pH >7
Blue litmus -red
Red litmus-blue
Reactive w/metals
Not reactive w/metals
H+ ions or H3O+ ions (hydronium)
OH- ions (hydroxide)
Conducts electricity
Corrosive

26. NaOH(s) + H2O → Na+1(aq) + OH-1(aq)
Naming Bases
A BASE is a substance that when put into water, gives away a hydroxide ion (OH-1) to another substance in the water solution.
NaOH(s) + H2O → Na+1(aq) + OH-1(aq)

27. Ex: NaOH Sodium hydroxide Naming Bases
1. Name the metal first and then the hydroxide ion
Ex: NaOH
Sodium hydroxide

28. Ex: KOH Potassium hydroxide Naming Bases
1. Name the metal first and then the hydroxide ion
Ex: KOH
Potassium hydroxide

29. Ex: Ca(OH)2 Calcium hydroxide Naming Bases
1. Name the metal first and then the hydroxide ion
Ex: Ca(OH)2
Calcium hydroxide

30. Ex: NH3 Ammonia It is a base because: NH3 + H2O → + NH4+1(aq) OH-1(aq)
Naming Bases
1. A base that is commonly used is
Ex: NH Ammonia
It is a base because:
NH3 + H2O → + NH4+1(aq) OH-1(aq)

31. Writing Chemical Formulas for Bases
Ex: sodium hydroxide
1. Write the chemical symbol f the metal, than OH
NaOH
2. Put up the charges, and criss-cross if necessary.
NaOH

32. Writing Chemical Formulas for Bases
Ex: calcium hydroxide
1. Write the chemical symbol f the metal, than OH
CaOH
2. Put up the charges, and criss-cross if necessary.
Ca(OH)2

33. Writing Chemical Formulas for Bases
Ex: lithium hydroxide
1. Write the chemical symbol f the metal, than OH
LiOH
2. Put up the charges, and criss-cross if necessary.
LiOH

34. Naming Acids
An ACID is a substance that when put into water, gives away a hydrogen ion (H+1) to another substance in the water solution.
HCl + H2O → H+1(aq) + Cl-1(aq)

35. Types of Acids There are two types of acids:
1. Binary acids-HCl(aq) two different elements
2. Ternary acids-H2SO4(aq)
-three different elements
-polyatomic ions (ending in ate)
-polyatomic ions (ending in ite)

36. Naming Binary Acids hydrochloric acid EX: HCl(aq)
1. Use the prefix hydro for hydrogen
2. Anion ending changes from ide to ic
3. Add the word acid at the end.
hydrochloric acid

37. Polyatomic ions ending in ate Polyatomic ions ending in ite
Naming Complex Acids
Polyatomic ions ending in ate
EX: H2SO4
1. NO hydro prefix!!!
2. Anion ending changes from ATE to IC
-Sulfate change to Sulfuric
“IC I ATE it”
3. Add the word acid at the end
Polyatomic ions ending in ite
EX: H2SO3
1. NO hydro prefix!!!
2. Anion ending changes from ITE to OUS
-Sulfite change to Sulfurous
“RITEOUS”
Add the word acid at the end
Polyatomic Ion
Name of Polyatomic ion
Acid formula
Name of acid

38. Polyatomic ions ending in ate
Naming Ternary Acids
Polyatomic ions ending in ate
EX: H2SO4
1. NO hydro prefix!!!
2. Anion ending changes from ATE to IC
-Sulfate change to Sulfuric
“IC I ATE that”
3. Add the word acid at the end
Sulfuric acid

39. Polyatomic ions ending in ite
Naming Ternary Acids
Polyatomic ions ending in ite
EX: H2SO3
1. NO hydro prefix!!!
2. Anion ending changes from ITE to OUS
-Sulfite change to Sulfurous
“RITEOUS”
Add the word acid at the end
Sulfurous acid

40. Practice Naming Acids 1. H3PO4(aq) Answer= Phosphoric acid 2. HNO2(aq)
-PO42- = phosphate
-Use saying “IC I ATE that”
Answer= Phosphoric acid
2. HNO2(aq)
-NO21- = nitrite
-Use saying “RITEOUS”
Answer= Nitrous acid

41. Writing Chemical Formulas for Acids

42. How to Write a Formula for an Acid:
BINARY ACIDS
Ex: hydrosulfuric acid
1. Write down symbols (H and S)
2. Determine Charges (H S-2)
3. Cancel charges or use criss-cross method
to form subscripts to cancel out charges
4. H2S(aq)

43. Ternary ACIDS
Ex: sulfuric acid
1. No hydro prefix so we have a polyatomic ion:
In this case “IC I ATE that”
sulfuric = sulfate (SO4)-2
Can also be “RITEOUS”
sulfurous = sulfite
2. Write down symbols (H and SO4)
3. Determine Charges (H SO4 -2)
4. Cancel charges or use criss-cross method
to form subscripts to cancel out charges
5. H2SO4(aq)