WorksheetsQuiz genchem II chapter 6
Total questions: 40
Worksheet time: 40mins
What ion is produced when an acid dissolves in water (Arrhenius definition)?
OH⁻
Na⁺
H₃O⁺
Cl⁻
According to Arrhenius, a base produces what in water?
H₃O⁺
OH⁻
CO₃²⁻
Cl⁻
3. What is a Brønsted-Lowry acid?
H⁺ acceptor
OH⁻ producer
H⁺ donor
Electron donor
Which of the following is amphoteric?
HCl
NaOH
H₂O
H₂SO₄
What is the conjugate base of H₂CO₃?
CO₃²⁻
HCO₃⁻
H₃O⁺
OH⁻
What does a strong acid do in water?
Forms a solid
Has low Ka
Partially dissociates
Completely dissociates
The pH of a neutral solution at 25°C is
7
14
0
10
What is the pH of a solution with [H₃O⁺] = 1 × 10⁻³ M?
1
3
10
7
What is the ion-product constant of water (Kw) at 25°C?
1.0
10
10⁻⁷
1.0 × 10⁻¹⁴
What is the relationship between pH and pOH?
pH + pOH = 7
pH + pOH = 10
pH + pOH = 14
pH × pOH = 14
Which of the following is a weak acid?
HCl
HNO₃
CH₃COOH
H₂SO₄
What is the pKa of an acid with Ka = 1.0 × 10⁻⁵?
5
–5
1
10
Which statement is TRUE about weak bases?
They fully dissociate
They form conjugate acids
They lower pH below 2
They have no OH⁻ ions
What is the pH of a 0.01 M NaOH solution?
2
12
7
1
What happens to solubility of a salt containing a weak base's conjugate acid in acidic solution?
Increases
Decreases
No change
Becomes zero
What is a buffer solution?
A solution that always has pH = 7
Strong acid + strong base
Weak acid + its conjugate base
Only strong base
What is the pH of pure water at 25°C?
1
7
10
14
Which compound below is a Brønsted-Lowry base?
HNO₃
NH₃
HCl
H₂SO₄
What does a large Ka value indicate?
Weak acid
No dissociation
Strong acid
Strong base
What is the color change range of phenolphthalein?
1–3
4–6
8.3–10.0
12–14
Which of the following can act as both a Brønsted-Lowry acid and base?
NH₄⁺
HCl
H₂O
NaOH
What is the conjugate acid of NH₃?
NH₄⁺
NH₂⁻
OH⁻
N₂
Which of the following species is amphiprotic?
HCl
HCO₃⁻
SO₄²⁻
Na⁺
Which pair is a correct conjugate acid-base pair?
H₂O and OH⁻
H₂SO₄ and SO₄²⁻
NH₄⁺ and NH₃
All of the above
A solution with [OH⁻] = 1 × 10⁻⁵ M has a pH of
5
7
9
10
What is the Ka of an acid if its pKa = 4.74?
1.82 × 10⁻⁵
5.50 × 10⁻⁴
3.00 × 10⁻³
1.00 × 10⁻⁷
What happens when HCl is added to a buffer solution of CH₃COOH/CH₃COO⁻?
pH increases sharply
pH remains constant
pH drops slightly
pH becomes 1
What is the main role of a buffer?
Maintain pH exactly at 7
Resist changes in pH
Increase acid strength
Neutralize all acids
A buffer is made from HF (weak acid) and NaF. Which component reacts with added base?
HF
Na⁺
F⁻
H₂O
If Ka = 1.8 × 10⁻⁵, what is pKa?
5.74
4.74
2.45
7.00
Which solution is more basic?
pH = 3
pH = 7
pH = 10
pH = 5
Which of the following affects the pH of a buffer?
Volume of solution
Temperature
Ratio [base]/[acid]
Indicator color
A weak acid has Ka = 1.0 × 10⁻⁶. What is the strength of its conjugate base?
Very weak
Moderate
Strong
Same as acid
Which of the following salts will make a solution basic?
NH₄Cl
NaNO₃
NaF
KBr
What is the pH at the equivalence point for strong acid–strong base titration?
3
7
10
Depends on indicator
In a weak acid–strong base titration, the equivalence point pH is:
< 7
= 7
> 7
Cannot be determined
What is the pH of a solution with [H₃O⁺] = 3.2 × 10⁻⁴ M?
3.49
4.00
2.00
5.00
What is the correct Kb expression for the base reaction of NH₃?
[NH₄⁺]/[OH⁻]
[NH₄⁺][OH⁻]/[NH₃]
[NH₃]/[NH₄⁺]
[NH₄⁺][NH₃]/[OH⁻]
Which compound is NOT a Brønsted-Lowry base?
NH₃
H₂O
Cl⁻
HNO₃
Which of the following best explains the common ion effect?
Adding more solvent to a solution
Adding a strong base to a weak base
Suppression of ionization by a shared ion
Using a neutral salt
