Chemistry Year 12 - Module 5 - Lesson 17

Solubility Product Ksp — Expressions & Calculations

Use this worksheet after reading the lesson to practise the key ideas and prove you can meet the success criteria.

Name
Date
Class

1. Key Ideas

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  • Ksp expressions have no denominator because the solid is omitted
  • Why Ksp alone does not always correctly rank solubility (stoichiometry matters)

2. Success Criteria

By the end, you should be able to:

  • Ksp expressions have no denominator because the solid is omitted
  • Molar solubility is the concentration of dissolved solute in mol/L
  • For 1:1 salts, s = √Ksp; for 1:2 salts, s = ∛(Ksp/4)

3. Key Terms

Dynamic equilibriumA state where forward and reverse reaction rates are equal.
Le Chatelier's PrincipleA system at equilibrium shifts to minimise applied disturbances.
Equilibrium constant (Keq)The ratio of product to reactant concentrations at equilibrium.
Reaction quotient (Q)The ratio of product to reactant concentrations at any instant.
Closed systemA system where neither matter nor energy can escape to surroundings.
Reversible reactionA reaction that can proceed in both forward and reverse directions.

4. Activity: Build the Lesson Map

Use the lesson to complete the table. Keep answers brief but specific.

PromptYour answer
Main concept
Important example
Common mistake to avoid
How this links to the next lesson

5. Short Answer Questions

1. Explain this lesson goal in your own words: "Ksp expressions have no denominator because the solid is omitted". Use one specific example from the lesson.

Band 32 marks

2. Apply this idea to a new example: "Molar solubility is the concentration of dissolved solute in mol/L". Show your reasoning clearly.

Band 43 marks

3. Analyse why this idea matters for understanding Solubility Product Ksp — Expressions & Calculations: "For 1:1 salts, s = √Ksp; for 1:2 salts, s = ∛(Ksp/4)".

Band 54 marks

6. Extend: Apply the Idea

Band 5/65 marks

A student gives a memorised answer about Solubility Product Ksp — Expressions & Calculations but does not use evidence or reasoning.

Improve the answer by writing a stronger response that uses accurate terminology, a relevant example and a clear explanation.

7. Multiple Choice

1. What is the best first step when answering a question about Solubility Product Ksp — Expressions & Calculations?

A. Identify the key concept being tested

B. Write every fact from memory

C. Ignore the command word

D. Skip examples and evidence

2. Which answer would show stronger understanding of Solubility Product Ksp — Expressions & Calculations?

A. An answer with accurate terms and reasoning

B. A copied definition only

C. A single-word response

D. An answer with no example

3. What should you do if a question asks you to explain?

A. Link the idea to a reason or cause

B. List unrelated facts

C. Only draw a diagram

D. Write the shortest possible answer

8. Success Criteria Proof

Finish with evidence that you can do each success criterion.

Success criterion 1

Prove that you can: Ksp expressions have no denominator because the solid is omitted

Band 32 marks
Success criterion 2

Prove that you can: Molar solubility is the concentration of dissolved solute in mol/L

Band 43 marks
Success criterion 3

Prove that you can: For 1:1 salts, s = √Ksp; for 1:2 salts, s = ∛(Ksp/4)

Band 54 marks

One thing I still need help with: