Count particles without changing the element
Use atomic and mass numbers to count protons, neutrons and electrons, and explain why making an ion does not change element identity.
Open the complete free lessonChemistry → Senior Secondary / GCSE / IGCSE / HS → Atomic Structure & Isotopes
Atomic structure, nuclear notation and models
FREE LESSON AVAILABLERelate proton/neutron/electron counts to atomic/mass number, charge and identity
Start with the right foundation.
- C01 matter
- integer arithmetic
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