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-IGCSE-27987, version v3.-4 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?

This version prints answers inline, followed by the full solutions and teacher pack pages.

Worksheet · TN-CHEM-IGCSE-27987 · v3.-4

Isotopes — Holiday Practice

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

FoundationNational Curriculum (UK)20 min37 marksAnswers included

Low-pressure spaced practice across the break.

Grade

IGCSE

Subject

Chemistry

Topic

Atomic Structure

Subtopic

Isotopes

Curriculum

National Curriculum (UK)

Difficulty

Foundation

Time

20 min

Questions

Total marks

Worksheet ID

TN-CHEM-IGCSE-27987

Version

v3.-4

Format

A4 · US Letter

Preview & download

Print-ready · high-resolution PDF · minimal ink

FreeMathWorksheet

Holiday Practice

TN-CHEM-IGCSE-27987 · v3.-4

Isotopes

IGCSE · Chemistry · Atomic Structure · National Curriculum (UK)

Grade

IGCSE

Subject

Chemistry

Topic

Atomic Structure

Subtopic

Isotopes

Curriculum

National Curriculum (UK)

Difficulty

Foundation

Time

20 minutes

Total marks

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

Write your name, your teacher's name and the date in the header.
Answer every question in the space provided. Continue on the back if needed.
Show all working — method marks are awarded even when the final answer is wrong.
Aim to finish in about 20 minutes.
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.Circle one fact you already know about isotopes.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Name one fact you already know about isotopes.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.

Recall

Bloom: Remember · 2 marks

Complete from memory. No calculator, no notes.

1.Complete the key term used in isotopes described here: item 1.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Define the key term used in isotopes described here: item 2.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.

FreeMathWorksheet · IGCSE Chemistry

Isotopes

Basic Practice

Bloom: Understand · 3 marks

Work through each item. Show the step you used.

1.Identify part 1 using the rule for isotopes.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Work out part 2 using the rule for isotopes.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.
3.Complete part 3 using the rule for isotopes.
[1]
AnswerAccept any correct response that applies the isotopes rule accurately.

Guided Practice

Bloom: Understand · 4 marks

The first step is given. Finish the reasoning.

1.Complete the method for part 1. Step 1 has been started for you.
[2]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Continue the working for part 2. Step 1 has been started for you.
[2]
AnswerAccept any correct response that applies the isotopes rule accurately.

Independent Practice

Bloom: Apply · 6 marks

No scaffolding. Set out your full method.

1.Determine part 1 on isotopes without help.
[2]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Solve part 2 on isotopes without help.
[2]
AnswerAccept any correct response that applies the isotopes rule accurately.
3.Determine part 3 on isotopes without help.
[2]
AnswerAccept any correct response that applies the isotopes rule accurately.

FreeMathWorksheet · IGCSE Chemistry

Isotopes

Challenge Questions

Bloom: Analyse · 6 marks

Harder items. Attempt every one, even partially.

1.Prove the statement in part 1 about isotopes.
[3]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Show that the statement in part 2 about isotopes.
[3]
AnswerAccept any correct response that applies the isotopes rule accurately.

Real-life Application

Bloom: Apply · 6 marks

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

1.Use the information to decide a real chemistry situation that depends on isotopes.
[3]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Use the information to decide a real chemistry situation that depends on isotopes.
[3]
AnswerAccept any correct response that applies the isotopes rule accurately.

Critical Thinking

Bloom: Evaluate · 8 marks

Explain your reasoning in full sentences.

1.Evaluate whether a student's method for isotopes is or is not efficient.
[4]
AnswerAccept any correct response that applies the isotopes rule accurately.
2.Explain why a student's method for isotopes is or is not efficient.
[4]
AnswerAccept any correct response that applies the isotopes rule accurately.

FreeMathWorksheet · IGCSE Chemistry

Isotopes

Reflection

Bloom: Create · 0 marks

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

1.Record how confident you feel with isotopes and what you will practise next.
[—]
AnswerStudent response — not marked.
2.Record how confident you feel with isotopes and what you will practise next.
[—]
AnswerStudent response — not marked.

FreeMathWorksheet

Answer key · Isotopes

Warm-up

1.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Recall

1.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Basic Practice

1.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
3.Accept any correct response that applies the isotopes rule accurately.[1]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Guided Practice

1.Accept any correct response that applies the isotopes rule accurately.[2]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[2]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Independent Practice

1.Accept any correct response that applies the isotopes rule accurately.[2]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[2]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
3.Accept any correct response that applies the isotopes rule accurately.[2]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Challenge Questions

1.Accept any correct response that applies the isotopes rule accurately.[3]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[3]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Real-life Application

1.Accept any correct response that applies the isotopes rule accurately.[3]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[3]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Critical Thinking

1.Accept any correct response that applies the isotopes rule accurately.[4]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Accept any correct response that applies the isotopes rule accurately.[4]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

Reflection

1.Student response — not marked.[0]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.
2.Student response — not marked.[0]
1. Recall the definition that underpins isotopes.
2. Apply it to the values or wording given in the question.
3. State the final answer clearly, with units or terminology where relevant.

FreeMathWorksheet

Teacher pack · Isotopes

Marking scheme

Band	Marks	Descriptor
Mastered	31–37	Applies isotopes fluently, including in unfamiliar contexts, with clear justification.
Secure	24–30	Reliable in routine questions; reasoning is mostly complete.
Developing	15–23	Secure in scaffolded items, inconsistent once support is removed.
Emerging	0–14	Needs re-teaching of the core rule before progressing.

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.

Question progression

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

01Warm-up
Answer quickly. These check you are ready for the topic.
Remember2 questions2 marks
02Recall
Complete from memory. No calculator, no notes.
Remember2 questions2 marks
03Basic Practice
Work through each item. Show the step you used.
Understand3 questions3 marks
04Guided Practice
The first step is given. Finish the reasoning.
Understand2 questions4 marks
05Independent Practice
No scaffolding. Set out your full method.
Apply3 questions6 marks
06Challenge Questions
Harder items. Attempt every one, even partially.
Analyse2 questions6 marks
07Real-life Application
Use the skill in context. State units in your answer.
Apply2 questions6 marks
08Critical Thinking
Explain your reasoning in full sentences.
Evaluate2 questions8 marks
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-IGCSE-27987, version v3.-4 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?: This version prints answers inline, followed by the full solutions and teacher pack pages.

Related resources

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