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Worksheet · TN-CHEM-A-LVL-36161 · v2.-2

Isotopes — Quick Practice

A single-focus worksheet on isotopes for A Level Chemistry. Nothing else from atomic structure is mixed in — every question, from warm-up to reflection, assesses this one objective and builds towards mastery.

FoundationEdexcel10 min37 marksNo answers on sheet

Ten minutes, one page, one skill.

Grade

A Level

Subject

Chemistry

Topic

Atomic Structure

Subtopic

Isotopes

Curriculum

Edexcel

Difficulty

Foundation

Time

10 min

Questions

20

Total marks

37

Worksheet ID

TN-CHEM-A-LVL-36161

Version

v2.-2

Format

A4 · US Letter

Preview & download

Print-ready · high-resolution PDF · minimal ink
FreeMathWorksheet

Quick Practice

TN-CHEM-A-LVL-36161 · v2.-2

Isotopes

A Level · Chemistry · Atomic Structure · Edexcel

Grade

A Level

Subject

Chemistry

Topic

Atomic Structure

Subtopic

Isotopes

Curriculum

Edexcel

Difficulty

Foundation

Time

10 minutes

Total marks

37

Student name

Teacher name

Date

Learning objectives

  • Recognise isotopes accurately in chemistry contexts.
  • Explain the underlying rule of isotopes in the student's own words.
  • Apply isotopes to multi-step and unfamiliar problems.
  • Justify a chosen method and identify errors in another student's work.

Skills assessed

  • Fluency and recall
  • Method and setting out
  • Reasoning and justification
  • Problem solving in context
  • Self-assessment

Instructions

  1. Write your name, your teacher's name and the date in the header.
  2. Answer every question in the space provided. Continue on the back if needed.
  3. Show all working — method marks are awarded even when the final answer is wrong.
  4. Aim to finish in about 10 minutes.
  5. Complete the reflection box at the end before you hand the sheet in.

Warm-up

Bloom: Remember · 2 marks

Answer quickly. These check you are ready for the topic.

  1. 1.Circle one fact you already know about isotopes.

    [1]
  2. 2.Name one fact you already know about isotopes.

    [1]

Recall

Bloom: Remember · 2 marks

Complete from memory. No calculator, no notes.

  1. 1.Label the key term used in isotopes described here: item 1.

    [1]
  2. 2.Complete the key term used in isotopes described here: item 2.

    [1]

FreeMathWorksheet · TN-CHEM-A-LVL-36161 · v2.-2

© 2026 FreeMathWorksheet. Licensed for classroom and home use. Redistribution or resale is not permitted.

Page 1 of 4

FreeMathWorksheet · A Level Chemistry

Isotopes

Basic Practice

Bloom: Understand · 3 marks

Work through each item. Show the step you used.

  1. 1.Match part 1 using the rule for isotopes.

    [1]
  2. 2.Work out part 2 using the rule for isotopes.

    [1]
  3. 3.Match part 3 using the rule for isotopes.

    [1]

Guided Practice

Bloom: Understand · 4 marks

The first step is given. Finish the reasoning.

  1. 1.Continue the working for part 1. Step 1 has been started for you.

    [2]
  2. 2.Continue the working for part 2. Step 1 has been started for you.

    [2]

Independent Practice

Bloom: Apply · 6 marks

No scaffolding. Set out your full method.

  1. 1.Calculate part 1 on isotopes without help.

    [2]
  2. 2.Calculate part 2 on isotopes without help.

    [2]
  3. 3.Solve part 3 on isotopes without help.

    [2]

FreeMathWorksheet · TN-CHEM-A-LVL-36161 · v2.-2

© 2026 FreeMathWorksheet. Licensed for classroom and home use. Redistribution or resale is not permitted.

Page 2 of 4

FreeMathWorksheet · A Level Chemistry

Isotopes

Challenge Questions

Bloom: Analyse · 6 marks

Harder items. Attempt every one, even partially.

  1. 1.Deduce the statement in part 1 about isotopes.

    [3]
  2. 2.Show that the statement in part 2 about isotopes.

    [3]

Real-life Application

Bloom: Apply · 6 marks

Use the skill in context. State units in your answer.

  1. 1.Apply a real chemistry situation that depends on isotopes.

    [3]
  2. 2.In context, work out a real chemistry situation that depends on isotopes.

    [3]

Critical Thinking

Bloom: Evaluate · 8 marks

Explain your reasoning in full sentences.

  1. 1.Explain why a student's method for isotopes is or is not efficient.

    [4]
  2. 2.Evaluate whether a student's method for isotopes is or is not efficient.

    [4]

FreeMathWorksheet · TN-CHEM-A-LVL-36161 · v2.-2

© 2026 FreeMathWorksheet. Licensed for classroom and home use. Redistribution or resale is not permitted.

Page 3 of 4

FreeMathWorksheet · A Level Chemistry

Isotopes

Reflection

Bloom: Create · 0 marks

Not marked. Answer honestly — this guides your next worksheet.

  1. 1.Describe how confident you feel with isotopes and what you will practise next.

    [—]
  2. 2.Describe how confident you feel with isotopes and what you will practise next.

    [—]

FreeMathWorksheet · TN-CHEM-A-LVL-36161 · v2.-2

© 2026 FreeMathWorksheet. Licensed for classroom and home use. Redistribution or resale is not permitted.

Page 4 of 4

Question progression

Recognition → understanding → application → reasoning → mastery. The ladder adapts to A Level, and every rung stays on isotopes only.

  1. 01Warm-up

    Answer quickly. These check you are ready for the topic.

    Remember2 questions2 marks
  2. 02Recall

    Complete from memory. No calculator, no notes.

    Remember2 questions2 marks
  3. 03Basic Practice

    Work through each item. Show the step you used.

    Understand3 questions3 marks
  4. 04Guided Practice

    The first step is given. Finish the reasoning.

    Understand2 questions4 marks
  5. 05Independent Practice

    No scaffolding. Set out your full method.

    Apply3 questions6 marks
  6. 06Challenge Questions

    Harder items. Attempt every one, even partially.

    Analyse2 questions6 marks
  7. 07Real-life Application

    Use the skill in context. State units in your answer.

    Apply2 questions6 marks
  8. 08Critical Thinking

    Explain your reasoning in full sentences.

    Evaluate2 questions8 marks
  9. 09Reflection

    Not marked. Answer honestly — this guides your next worksheet.

    Create2 questions0 marks

Answer key & solutions

Every worksheet auto-generates a complete key with step-by-step solutions, the marking scheme and teacher notes. It prints as separate pages so the student copy stays clean.

Teacher notes

  • Set the warm-up as a five-minute starter; it diagnoses readiness for isotopes before you teach.
  • Guided practice is the pivot point — circulate here rather than during independent practice.
  • Mark the reasoning questions with the marking scheme bands, not raw totals, so progress is comparable across variants.
  • Students who band Emerging should repeat the Easy variant of this same subtopic before moving on within Atomic Structure.

Common student mistakes

  • Confusing isotopes with a neighbouring idea in atomic structure.

Teaching tips

  • Model one worked example of isotopes under a visualiser before handing the sheet out.
  • Ask students to predict which question they will find hardest, then check the prediction afterwards.
  • Pair Developing students with Secure students for the guided practice block only.
  • Use the answer key as a self-marking station rather than collecting the sheets in.

Extension activities

  • Challenge worksheet on isotopes with justification-only questions.
  • Design your own isotopes question and write the mark scheme for it.
  • Link isotopes to the next subtopic in Atomic Structure and explain the connection.
  • Ten-minute timed practice to convert accuracy into fluency.

Switch version

Same subtopic · same objectives · different job

Frequently asked

What exactly is in the download?
A 20-question, 37-mark sheet with branded header, objectives, skills, instructions, name and date fields, page numbering, footer branding, copyright, worksheet ID TN-CHEM-A-LVL-36161, version v2.-2 and a QR code back to this page.
Does it print correctly on US Letter?
Yes. Switch paper size in the download panel — margins and typography are identical, so nothing reflows or clips.
Is the answer key included?
The student copy prints clean. Toggle answers on to append the answer key, marking scheme and teacher pack.

Related resources

Tutoring

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