Atomic Model Timeline

Explore how atomic models changed over time

1803

Dalton's Solid Sphere

Atoms are indivisible, solid spheres. Each element has identical atoms.

1897

Thomson's Plum Pudding

Atoms contain negatively charged electrons embedded in positive matter.

1911

Rutherford's Nuclear Model

Most mass is concentrated in a tiny, dense nucleus. Electrons orbit.

1913

Bohr's Electron Shells

Electrons orbit in fixed energy levels (shells) around the nucleus.

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