12
Questions to discuss
Multiple-choice, true/false and short numerical answers. No speed bonuses or formal grade claims.
ORIGINAL BRAINJOY MINI-UNIT / FREE SAMPLE
Particle detectives
Atoms, ions and isotopes. Follow the clues, count the particles and explain the charge.
An original secondary introduction with student worksheets, teacher explanations and reusable digital questions. A 45-minute teaching outline is included. Adapt it for your learners and curriculum; this is not an official exam-board pack or a validated assessment.
4
Printable pages
Two student pages, plus two teacher pages with a lesson outline, support ideas and answers with reasons.
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Student copies and the teacher key are separate files. Check each file before sharing. Nothing you type is collected by these resource pages.
Open student worksheetsStudent PDF (2 pages)Teacher guide and keyTeacher PDF (2 pages, includes answers)
Use the questions your way
Edit worksheet formattingOpen 12 flashcardsShared-screen team reviewQuiz JSON (includes answers)Download classroom bundle
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Teaching notes and sources
Particle rules and ordinary ion formation were checked against OpenStax Chemistry 2e, section 2.3 and section 2.6 on November 10, 2026. The questions, teaching activities, explanations, layout and decorative illustration are original BrainJoy work. No source images or question text have been copied. No publisher endorsement is implied.
Free for your own classroom or home use and adaptation. Do not resell or redistribute as your own product. Teacher review required. These permissions apply to this mini-unit only and do not change the rights of other site resources.