pKa (AQA A-Level Chemistry): Quizzes

📚Quizzes
Revision NotesModel AnswersQuizzesFlashcardsExam Questions
pKa
Sign up to keep practising.Create a free account to play more quizzes and track your progress.

Practise the questions

10 questions from this quiz

Show

What does pKapK_a provide a logarithmic measure of?

Acid strength

Which formula correctly relates pKapK_a to KaK_a?

pKa=−log⁡10KapK_a = -\log_{10} K_a

How do you calculate KaK_a from pKapK_a?

Ka=10−pKaK_a = 10^{-pK_a}

For weak acids, what assumption is made about dissociation?

Dissociation is minimal

What is the formula to estimate [H+][\text{H}^+] for a weak acid?

[H+]=Ka×[HA][\text{H}^+] = \sqrt{K_a \times [\text{HA}]}

What is the pKapK_a if Ka=1.8×10−5K_a = 1.8 \times 10^{-5}?

4.74

What is [H+][\text{H}^+] for 0.105 M ethanoic acid with Ka=1.74×10−5K_a = 1.74 \times 10^{-5}?

1.35×10−31.35 \times 10^{-3} M

How do you find [H+][\text{H}^+] from pH?

[H+]=10−pH[\text{H}^+] = 10^{-\text{pH}}

At the half-equivalence point in titration, what relationship holds?

pH=pKa\text{pH} = pK_a

What is true about concentrations at the half-equivalence point?

[HA]=[A−][\text{HA}] = [\text{A}^-]

Explore AQA A-Level Chemistry Revision Notes by Topics

Thermodynamics (A Level only)

Rate Equations (A Level only)

Equilibrium constant (Kp) for Homogeneous Systems (A Level only)

Electrode Potentials & Electrochemical Cells (A Level only)

Fundamentals of Acids & Bases (A Level only)

Further Acids & Bases Calculations (A Level only)

Explore AQA A-Level Chemistry Model Answers by Topics

Thermodynamics (A Level only)

Rate Equations (A Level only)

Equilibrium constant (Kp) for Homogeneous Systems (A Level only)

Electrode Potentials & Electrochemical Cells (A Level only)

Fundamentals of Acids & Bases (A Level only)

Further Acids & Bases Calculations (A Level only)

Explore AQA A-Level Chemistry Flashcards by Topics

Thermodynamics (A Level only)

Rate Equations (A Level only)

Equilibrium constant (Kp) for Homogeneous Systems (A Level only)

Electrode Potentials & Electrochemical Cells (A Level only)

Fundamentals of Acids & Bases (A Level only)

Further Acids & Bases Calculations (A Level only)

Explore AQA A-Level Chemistry Exam Questions by Topics

Thermodynamics (A Level only)

Rate Equations (A Level only)

Equilibrium constant (Kp) for Homogeneous Systems (A Level only)

Electrode Potentials & Electrochemical Cells (A Level only)

Fundamentals of Acids & Bases (A Level only)

Further Acids & Bases Calculations (A Level only)

Join 100,000+ A-Level students studying Quizzes with us.

Select your subjects, and get access to A+ resources today.