1. Acid-Base Pairs H2O + NH3  OH- + NH4+ acid base base acid
H2O/OH- are an acid-base pair
hydroxide ion is the conjugate base of water
NH4+/NH3 are an acid-base pair
ammonium ion is the conjugate acid of ammonia

2. HClO 4 + H2O  H3O+ + ClO4-
acid: HClO4
conjugate base: ClO4-
HClO4/ClO4- are an acid-base pair
base: H2O
conjugate acid: H3O+
H3O+/H2O are an acid-base pair
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H2O + H2O  H3O+ + OH-
acid: H2O
conjugate base: OH-
H2O/OH- are an acid-base pair

3. conjugate acid-base pairs
acid: HCl
conjugate base of HCl: Cl-
acid: H2SO4
conjugate base of H2SO4: HSO4-
acid: NH3
conjugate base of NH3: NH2-
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base: NH3
conjugate acid of NH3: NH4+
base SO42-
conjugate acid of SO42-: HSO4-

4. The stronger the acid, the weaker is it’s conjugate base
The weaker the acid, the stronger is it’s conjugate base
The stronger the base, the weaker is it’s conjugate acid
The weaker the base, the stronger is it’s conjugate acid
Strong acid HI > HBr > HCl >> HF Weak acid
Strong Base F- >> Cl- > Br - > I Weak Base
Acid strength depends on bond strength & stability of the resulting anion: HF  H+ + F -
Table 10-2

5. Ternary Acids
Ternary Acid - An acid that contains hydrogen, oxygen and a non-metal
most ternary acids are hydroxyl compounds of nonmetals (oxoacids): HNO3 can also be written as HONO2
H2SO4 can also be written as (OH)2SO2 .. .. O || N .. .. O O H .. .. ..
hydroxyl
groups
hydroxyl group

6. Acid Strength of Ternary Acids
HNO3  H+ + NO3-
Why does nitric acid lose a proton instead of a hydroxide ion?
The E.N. = 0.5 (N & O) and 1.4 (O & H)
Why is HNO3 a strong acid and HNO2 (HONO) a weak acid?
look at the ox. # Nitric Acid N +5 ox. state Nitrous Acid N +3 ox. state .. .. O || N
3.0
3.0 .. N
3.5
3.5 ..
2.1 ..
2.1 .. O O H .. .. .. O O .. .. .. H
hydroxyl group
hydroxyl group

7. Acid Stregth of HClOx series x= 1, 2, 3 or 4
hypochlorous, chlorous, chloric and perchloric acid
HClO HClO HClO HClO4
HClO4 >> HClO3 > HClO2 > HClO
What does this tell us about their conjugate bases?
ClO4- << ClO3- < ClO2- < ClO -

8. Make a hypothesis on the acid strength of HBrO3 compared to HIO3
Br and I are in the same oxidation state (+5)
The ternary acid with the most electronegative non-metal
will be the most acidic
HBrO3 > HIO3

9. Acidic Salts & Basic Salts
Normal Salt - A salt that doesn’t have ionizable hydrogens or hydroxyl groups.
Acidic Salt - A salt that has ionizable hydrogens but, doesn’t necesarily produce acidic solutions.
H2CO3 + NaOH  NaHCO3 + H2O
H2CO3 + OH-  HCO3- + H2O
Polyprotic Acid rxn w/ < stoich. amount of SB gives an acidic salt

10. Fe(OH)2(s) + HCl  Fe(OH)Cl(s) + H2O
Basic Salt - A salt that has basic hydroxyl groups but doesn’t necesarily create basic solutions.
Fe(OH)2(s) + HCl  Fe(OH)Cl(s) + H2O
Fe(OH)2(s) + H+ + Cl-  Fe(OH)Cl(s) + H2O
polyhydroxy base rxn w/ < stoich. amount of SA gives a basic salt

11. Preparation of Acids Binary Acids - hydrogen halides
nonvolatile salt of  salt of volatile acid volatile acid nonvolatile acid acid
H2SO4 + NaF(s)  NaHSO4 + HF(g)
H3PO4 + NaBr(s)  NaH2PO4 + HBr(g)
Ternary Acids
nonmetal oxide + water  ternary acid
N2O5(s) + H2O  2HNO3
Binary & Ternary Acids
PX3 + 3H2O  H3PO3 + 3HX
PX5 + 4H2O  H3PO4 + 5HX