1. 6.1 Theories of Acids and Bases A. Naming Acids and Bases
Chapter 6: Acids & Bases
6.1 Theories of Acids and Bases
A. Naming Acids and Bases
acids always have as the state and always have
(aq)
hydrogen
Rules
1. hydrogen becomes acid
2. hydrogen becomes acid
3. hydrogen becomes acid
____ide
hydr____ic
_____ate
_____ic
____ite
____ous

2. Examples: 1. hydrogen iodide = hydroiodic acid phosphoric acid
Change each of the following to the appropriate acid name and give the formula:
1. hydrogen iodide =
hydroiodic acid
HI(aq)
phosphoric acid
H3PO4(aq)
2. hydrogen phosphate =
3. hydrogen nitrite =
nitrous acid
HNO2(aq)
4. hydrogen sulphite =
sulphurous acid
H2SO3(aq)

3. sodium hydrogen carbonate
most bases are ionic compounds that are named accordingly
Examples:
Name each of the following bases:
1. NaOH(aq) =
sodium hydroxide
2. NaHCO3(aq) =
sodium hydrogen carbonate
3. Mg(OH)2(aq) =
magnesium hydroxide
4. NH3(aq) =
ammonia

4. aqueous hydrogen iodide
IUPAC names for acids and bases are simply the word “aqueous” followed by the ionic name
Examples:
Write the IUPAC name for each of the following acids and bases:
1. hydroiodic acid =
aqueous hydrogen iodide
2. magnesium hydroxide =
aqueous magnesium hydroxide
3. sulphurous acid =
aqueous hydrogen sulphite
4. sodium hydrogen carbonate =
aqueous sodium hydrogen carbonate

5. B. Properties of Acids and Bases
are of a substance
empirical properties
observable properties
acids, bases and neutral substances have some properties that distinguish them and some that
are the same

6. Acids Bases Neutral Substances sour taste bitter taste electrolytes
electrolytes, non-electrolytes
neutralize
bases
neutralize
acids
react with
indicators
do not
react with
indicators
affect indicators the same way
litmus -
red
litmus -
blue
bromothymol blue -
yellow
bromothymol blue -
blue
phenolphthalein -
phenolphthalein -
pink
colourless
react with to produce
metals
H2(g) pH
greater than 7
less than 7 pH pH
of 7
eg)
HCl(aq), H2SO4(aq)
eg)
Ba(OH)2(aq) NH3(aq)
eg)
NaCl(aq), Pb(NO3)2(aq)

7. C. Arrhenius Definition
first proposed theory on acids and bases
Svante Arrhenius
his theory was that some compounds form
electrically charged particles
when in
solution
his explanation of the properties of acids and bases is called the
Arrhenius theory of acids and bases

8. an Arrhenius is a substance that (because it is molecular) to form
acid
ionizes
hydrogen ions, H+(aq), in water
an will in an aqueous solution
acid
increase the [H+(aq)]
an Arrhenius is a substance that to form in water
base
dissociates
hydroxide ions, OH(aq),
a will in an aqueous solution
base
increase the [OH-(aq)]

9. D. Modified Arrhenius Definition
the original definition of acids and bases proposed by Arrhenius is good but it has
limitations
some substances that might be predicted to be are actually
neutral
basic
eg)
Na2CO3(aq), NH3(aq)
it has been found that not all bases contain the
hydroxide ion
as part of their
chemical formula

10. an Arrhenius is a substance that in aqueous solution
base (modified)
reacts with water
to produce
OH(aq) ions
eg) 
NH3(aq) +
H2O()
NH4+(aq) +
OH(aq)

11. when acids ionize, they produce
H+(aq)
eg) HCl(g)  H+(aq) + Cl(aq)
it has been found using analytical technology like X-ray crystallography that in an aqueous solution
H+(aq) ions do not exist in isolation
the hydrogen ion is extremely positive in charge and water molecules themselves are very polar so… it is that would exist in water without being attracted to the of other
highly unlikely
hydrogen ions
negative poles
water molecules

12. this results in the formation of the
hydronium ion +
H3O+(aq)

13. an Arrhenius is a substance that in aqueous solution
acid (modified)
reacts with water
to produce
H3O+(aq) ions
eg) 
HCl(aq) +
H2O()
Cl(aq) +
H3O+(aq) 
H2SO3(aq) +
H2O()
HSO3(aq) +
H3O+(aq)
SO2 ()
H2O()

14. 6.2 Strong and Weak Acids and Bases
the of a substance depend on two things:
acidic and basic properties 1.
the of the solution
concentration 2.
the of the acid or base
identity

15. A. Strong Acids and Weak Acids
an acid that ionizes almost in water is called a
100%
strong acid
eg) HCl(aq) + H2O() 
H3O+(aq) +
Cl(aq)
100% of the becomes
H3O+(aq) and Cl(aq)
HCl(aq)
the concentration of the is the as the concentration of the it came from
H3O+(aq)
same
acid
strong acids are
strong electrolytes and
react vigorously with metals

16. there are 6 strong acids:
perchloric acid
HClO4(aq)
hydrobromic acid
HBr(aq)
hydroiodic acid
HI(aq)
hydrochloric acid
HCl(aq)
sulfuric acid
H2SO4(aq)
nitric acid
HNO3(aq)
***on your periodic table

17. ⇌ a and only a small percentage of the acid forms
weak acid does not ionize 100%
ions in solution
eg)
CH3COOH(aq) + H2O() ⇌
H3O+(aq) +
CH3COO(aq)
we use the for weak acids
equilibrium arrow
weak acids are
react much less vigorously with metals
weak electrolytes and

18. B. Strong Bases and Weak Bases
a base that dissociates into ions in water is called a
100%
strong base
are strong bases
ionic hydroxides and metallic oxides
eg) NaOH(aq) 
Na+(aq) +
OH(aq)
a and only a small percentage of the base forms
weak base does not dissociate 100%
ions in solution +
eg) NH3(aq) + H2O() ⇌
NH4+(aq)
OH(aq)
we use the for weak bases
equilibrium arrow

19. C. Monoprotic and Polyprotic Acids
acids that have only per molecule that can are called
one hydrogen atom
ionize
monoprotic acids
eg)
HCl(aq),
HF(aq),
HNO3(aq),
CH3COOH(aq)
monoprotic acids can be
strong or weak

20. acids that contain that can are called
two or more hydrogen atoms
ionize
polyprotic acids
eg)
H2SO4(aq),
H3PO4(aq)
acids with are , with are
two hydrogens
diprotic
three hydrogens
triprotic

21. when polyprotic acids ionize, only hydrogen is removed at a time, with each acid becoming
one
progressively weaker
eg) 
H2SO4(aq) +
H2O()
H3O+(aq) +
HSO4(aq)
HSO4(aq) +
H2O() 
H3O+(aq) +
SO42(aq)

22. D. Monoprotic and Polyprotic Bases
bases that are called
react with water in only one step to form hydroxide ions
monoprotic bases
eg) NaOH(s)
bases that react with water in are called
two or more steps
polyprotic bases
eg) CO32(aq), PO43(aq)
***complex ions with more than 1- charge!!!

23. as with polyprotic acids, only
OH(aq) is formed at a time, and each new base formed is than the last
one
weaker
eg) 
CO32(aq) +
H2O()
OH(aq) +
HCO3(aq)
HCO3(aq) +
H2O() 
OH(aq) +
H2CO3(aq)

24. E. Neutralization the reaction between an acid and a base produces an
ionic compound and water
acid +
base
a salt +
water →
eg) HCl(aq) + KOH(aq) →
KCl(aq) + HOH()
the products of are both
neutralization
neutral
in a neutralization reaction or between a , the product is always
acid-base reaction
strong acid and a strong base
water
H3O+(aq) +
OH(aq) 
2 H2O()

25. F. Acid and Base Spills
there are many uses for both acids and bases in our households and in industry
due to their, special care must be used when they are being
reactivity and corrosiveness
produced and transported

26. the two ways to deal with acid or base spills are:
1. dilution:
reduce the by adding
concentration
water
2. neutralization:
you always use a for the neutralization so you aren’t left with another hazardous situation
weak acid or base

27. A. Ion Concentration in Water
6.3 Acids, Bases and pH
A. Ion Concentration in Water
the “self-ionization” of water is very
small
(only 2 in 1 billion)
H2O() +
H2O() 
H3O+(aq) +
OH-(aq)
the concentration of and are
hydronium ions
equal and constant in pure water
hydroxide ions
[H3O+(aq)]=
[OH-(aq)] =
1.0 x 10-7 mol/L
1.0 x 10-7 mol/L

28. B. The pH Scale in 1909, Soren Sorenson devised the pH scale
it is used because the [H3O+(aq)] is
very small
at 25C (standard conditions), most solutions have a pH that falls between
0.0 and
14.0
it is possible to have a pH and a pH
negative
above 14
it is a based on whole numbers that are powers of 10
logarithmic scale

29. more acidic more basic neutral
there is a for every change in on the pH scale
10-fold change in [H3O+(aq)] 1
eg)
a solution with a pH of 11 is times more basic than a solution with a pH of 9
10  10 = 100
pH Scale
more acidic
more basic 7 14
neutral

30. C. Calculating pH and pOH
pH =  log [H3O+(aq)]
***New sig dig rule:
when reporting pH or pOH values, only the numbers to the count as significant
right of the decimal place
Try These:
1.     [H3O+(aq)] = 1 x mol/L pH =
2.     [H3O+(aq)] = 1.0 x 10-2 mol/L pH =
3.     [H3O+(aq)] = 6.88 x 10-3 mol/L pH =
4.     [H3O+(aq)] = 9.6 x 10-6 mol/L pH =
10.0
2.00
2.162
5.02

31.  H+(aq) + NO3-(aq) HNO3(aq) pH = -log[H+(aq)] = -log[0.133… mol/L]
Example
6.30 g of HNO3 is dissolved in 750 mL of water. What is the pH ? 
H+(aq) +
NO3-(aq)
HNO3(aq)
m = 6.30 g
M = g/mol
V = L
c = 0.133…mol/L x 1/1
= 0.133…mol/L
n = m M
= 6.30 g
63.02 g/mol
= …mol
pH = -log[H+(aq)]
= -log[0.133… mol/L]
= 0.875
c = n V
= …mol
0.750 L
= 0.133…mol/L

32. just as deals with deals withpH
[H3O+(aq)],
pOH
[OH(aq)]
***p just means log
at SATP…
pH + pOH = 14 pH 1 3 5 7 9 11 13 14 14 13 11 9 7 5 3 1
pOH

33. to calculate the use the same formulas as pH but substitute the
pOH,
[OH(aq)]
pOH =  log[OH(aq)]
Try These:
1.     [OH(aq)] = 1.0  mol/L pOH =
2.     [OH(aq)] =  10-2 mol/L pOH =
3.     [OH(aq)] =  10-6 mol/L pOH =
4.     [OH(aq)] = 2  10-6 mol/L pOH =
11.00
1.206
5.0264
5.7

34. you could also be given the pH or pOH and asked to calculate the
[H3O+(aq)] or [OH-(aq)]
[H3O+(aq)] = 10-pH
[OH(aq)]= 10-pOH

35. Try These:
1.     pH [H3O+(aq)] =
2.     pH [H3O+(aq)] =
3.     pH [H3O+(aq)] =
4.     pH 7 [H3O+(aq)] =
5.     pOH 1.0 [OH(aq)] =
6.     pOH 13.2 [OH(aq)] =
7.     pOH 6.90 [OH(aq)] =
8.     pOH [OH(aq)] =
1 x 10-4 mol/L
6.2 x mol/L
3.98 x mol/L
10-7 mol/L
0.1 mol/L
6  mol/L
1.3  mol/L
mol/L

36. 9. Complete the following table:
[H3O+(aq)]
[OH(aq)] pH
pOH
Acid/Base/
Neutral
4.0 x 10-6 mol/L
2.5 x 10-9 mol/L
5.40
8.60
acid
9.500
4.500
base
3.16 x mol/L
3.16 x 10-5 mol/L
3.30
10.70
5.0 x 10-4 mol/L
2.0  1011 mol/L
acid
10 mol/L
1.0 x mol/L
-1.00
15.00
acid
base
1.0 x mol/L
10 mol/L
15.00
-1.00
1.36
base
2.3 x mol/L
0.044 mol/L
12.64

37. D. Measuring pH Indicators pH can be measured using :
1. acid-base indicators
2. pH meter
Indicators
an is any chemical that in an acidic or basic solution
acid-base indicator
changes colour
they can be
dried onto strips of paper
eg) litmus paper, pH paper

38. they can be
solutions
eg) bromothymol blue, universal indicator, indigo carmine etc
they can be made from
natural substances
eg) tea, red cabbage juice, grape juice

39. each indicator has a where it will
specific pH range
change colour
you can use to approximate the
two or more indicators
pH of a solution

40. pH Meters using a pH meter is the most way of measuring precise pH
it has an that compares the [H3O+(aq)] in the solution to a and it will give a of the pH
electrode
standard
digital readout

41. E. Diluting an Acid or Base
when you to an , you change the
add water
acid or base
[H3O+(aq)] or the [OH(aq)]
diluting an acid will the until a pH of is reached
decrease
[H3O+(aq)]
7.0
diluting a base will the until a pH of is reached
decrease
[OH-(aq)]
7.0

42. Remember: CiVi = CfVf
A concentrated solution is made by dissolving 5g of HCl into 30 L of water. You then take 10 mL of this solution and dilute it to a volume of 50 L. What is the pH of the diluted solution?

43. Formulas to remember:
pH = - log [H3O+]
pOH = - log [OH-]
[H3O+] = 10-pH
[OH-] = 10-pOH
C = n/v
CiVi = CfVf

44. Review Assignment:
Textbook p. 244 #1-28