Isotopes

Explain isotopes as atoms of the same element with different numbers of neutrons, identify them from notation and see why relative atomic masses are not whole numbers.

⏱ 18 min❓ 9 questions

What you'll be able to do

✔I can define isotopes and identify them from nuclear notation
✔I can explain why isotopes of an element have the same chemical properties
✔I can calculate a relative atomic mass as a weighted average of isotopes

How this works

1Read the short explanations first — they teach you what you need before each question.
2Answer each question, then tap Check. A right answer moves you on automatically; if it's wrong, you'll see a friendly explanation of why.
3Finish all 3 steps to see your score — sign in and subscribe to unlock the full lesson and save it.

What's inside

9 questions and 1 quick teaching card, including:

✅Select all that apply — More than one can be right — pick every option that fits.
🔘Multiple choice — Tap the answer you think is best, then check it.

👪Grown-up tip: sit alongside younger learners for the first few lessons. Read the questions together and chat about the explanations — that's where the real learning sticks.

Curriculum: AC9S9U05