Chapter 8

Question 1

Li+, Na+, K+, and NH4+

Answer 1

Compounds containing these the following ions are generally soluble

Exceptions:

None

Question 2

NO3-, and C2H302-

Answer 2

Compounds containing these the following ions are generally soluble

Exceptions:

None

Question 3

Cl-, Br-, and I-

Answer 3

Compounds containing these the following ions are generally soluble

Exceptions:

When paired with Ag+, Hg2(2+), Pb(2+) the resulting compounds are insoluble

Question 4

SO4(2-)

Answer 4

Compounds containing these the following ions are generally soluble

Exceptions:

When paired with Sr2+, Ba2+, Pb2+, Ag+, or Ca2+ the resulting compounds are insoluble

Question 5

OH- and S2-

Answer 5

Compounds containing these the following ions are generally insoluble

Exceptions:

When these ions paired with Li+, Na+, K+, or NH4+ the resulting compounds are soluble

When S2- is paired with Sr2+, Ba2+, or Ca2+ the resulting compound is soluble

When OH- is paired with Sr2+, Ba2+, or Ca2+ the resulting compound is soluble

Question 6

CO3(2-) and PO4(3-)

Answer 6

Compounds containing these the following ions are generally insoluble

Exceptions:

When these ions paired with Li+, Na+, K+, or NH4+ the resulting compounds are soluble

Question 7

HBr

Answer 7

Hydrobromic acid

Question 8

HCl

Answer 8

Hydrochloric acid

Question 9

HI

Answer 9

Hydroiodic acid

Question 10

HNO 3

Answer 10

Nitric acid

Question 11

HClO 4

Answer 11

Perchloric acid

Question 12

H 2 SO 4

Answer 12

Sulfuric acid

Question 13

HF

Answer 13

Hydrofluoric acid (weak acid)

Question 14

NaOH

Answer 14

Sodium hydroxide

Question 15

HCH 2 COOH

Answer 15

Acetic acid (weak acid)

Question 16

LiOH

Answer 16

Lithium hydroxide

Question 17

KOH

Answer 17

Potassium hydroxide

Question 18

Ca(OH) 2

Answer 18

Calcium hydroxide

Question 19

Ba(OH) 2

Answer 19

Barium hydroxide

Question 20

NH 3

Answer 20

Ammonia (weak base)

Question 21

Compound That Undergo Gas-Evolution Reaction: sulfide

Answer 21

Intermediate Product: None

Gas Evolved: H2S

Example: 2 HCl (aq) + K2S (aq) → H2S (g) + 2 KCl (aq)

Question 22

Compound That Undergo Gas-Evolution Reaction: carbonates and bicarbonates

Answer 22

Intermediate Product: H2CO3

Gas Evolved: CO2

Example:

2 HCl (aq) + K2CO3 (aq) → H2CO3 (aq) + 2 KCl (aq)

Final Equation:
2 HCl (aq) + K2CO3 (aq) → H2O (l) + CO2 (g) + 2 KCl (aq)

Question 23

Compound That Undergo Gas-Evolution Reaction: sulfites and bisulfites

Answer 23

Intermediate Product: H2SO3

Gas Evolved: SO2

Example:

2 HCl (aq) + K2SO3 (aq) → H2SO3 (aq) + 2 KCl (aq)

Final Equation:
2 HCl (aq) + K2SO3 (aq) → H2O (l) + SO2 (g) + 2 KCl (aq)

Question 24

Compound That Undergo Gas-Evolution Reaction: ammonia

Answer 24

Intermediate Product: NH4OH

Gas Evolved: NH3

Example:

NH4Cl (aq) + KOH (aq) → NH4OH (aq) + 2 KCl (aq)

Final Equation:
NH4Cl (aq) + KOH (aq) → H2O (l) + NH3 (g) + 2 KCl (aq)

Question 25

Rules for assigning oxidation states

Answer 25

1. The oxidation state of an atom in a free element is 0.
2. The oxidation state of a monoatomic ion is equal to its charge.
3. The sum of the oxidation states of all atoms in:

• a neutral molecule or formula unit is 0.
• an ion is equal to the charge of the ion.

4. In their compounds, metals have positive oxidation states.

• Group 1A metals always have an oxidation state of +1.
• Group 2A metals always have an oxidation state of +2.

5. In their compounds, we assign nonmetals oxidation states according to the table on the right. Entries at the top of the table take precedence over entries at the bottom of the table.

Question 26

Oxidation State: Fluorine

Answer 26

-1

Question 27

Oxidation state: Hydrogen

Answer 27

+1

Question 28

Oxidation state: Oxygen

Answer 28

-2

Question 29

Oxidation state: Group 7A

Answer 29

-1

Question 30

Oxidation State: Group 6A

Answer 30

-2

Question 31

Oxidation State: Group 5A

Answer 31

-3