Concept Map

Last updated at July 16, 2026 by

The Atom Atomic Models Dalton → indivisible Thomson → plum pudding Rutherford → nucleus Bohr → energy levels Subatomic Particles Electron (−1) Proton (+1) Neutron (0) Atomic Notation Atomic number Z Mass number A A = p + n Electrons & Beyond 2n² rule, octet Valency Isotopes / Isobars
The Atom
↓
Atomic Models
Dalton → indivisible
Thomson → plum pudding
Rutherford → nucleus
Bohr → energy levels
Subatomic Particles
Electron (−1)
Proton (+1)
Neutron (0)
Atomic Notation
Atomic number Z
Mass number A
A = p + n
Electrons & Beyond
2n² rule & octet
Valency
Isotopes / Isobars
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