Exploring Atomic Models and Theories in Science

Dalton's Atomic Theory

He pictured atom as solid, indestructible with a mass like a billiard ball. His contribution: foundation of modern physical science.

Dalton's Atomic Theory Postulates

Matter is made of small, indivisible atoms. Elements have identical atoms, different from other elements. Compounds contain atoms in fixed ratios. Chemical reactions rearrange atoms, no creation or destruction.

Joseph John Thomson

Experimented with a vacuum tube. Discovered the negatively charged electron using the cathode ray tube.

Joseph John Thomson's Theory

Proposed that atoms consist of subatomic particles with electric charges. Described the electron as embedded in a positively charged mass, like raisins in bread.

Ernest Rutherford

Tested Thompson's theory using a thin sheet of gold foil. Discovered that most α (alpha) particles passed through the foil, while some were deflected.

Ernest Rutherford's Conclusion

Concluded that atoms are mostly empty space with a positive nucleus. Coined the term 'nucleus' for the central core of an atom.

Ernest Rutherford

Proposed a model where electrons orbit the nucleus, resembling a miniature solar system.

Nuclear Model of an Atom

Called the nuclear model due to the discovery of the nucleus.

Niels Bohr

Danish Physicist who proposed that electrons in an atom can travel in specific orbits without radiating energy.

Quanta

Discrete energy packages that electrons can gain or lose to change orbits.

Planetary Model of an Atom

Explains the stability of atoms by incorporating Max Planck's quantum theory.

Energy Loss in Rutherford's Model

Addressed by Niels Bohr in his atomic model.

Restricted Orbits

Electrons can travel around the nucleus without radiating energy, provided they remain in certain restricted orbits.

Bohr-Sommerfeld Atomic Model

Enhanced Bohr's original model by introducing the concept of elliptical orbits.

Arnold Sommerfeld

German theoretical physicist who contributed to the Bohr-Sommerfeld model.

Elliptical Orbits

Electrons move in elliptical, rather than circular orbits, as introduced by Sommerfeld.

Bohr-Sommerfeld Atomic Model

This atomic model expanded upon the Bohr model and introduced the concept of elliptical orbits for electrons.

Nuclear Model of an Atom

Ernest Rutherford's atomic model, which is based on the discovery of the nucleus.

The Discovery of the Electron

The main discovery of J.J. Thomson's experiments with cathode rays.

Niels Bohr

Whose atomic model introduced the concept of electron energy levels or shells.

John Dalton

According to this physicist, atoms are indivisible and cannot be broken down into smaller parts.

Planetary Model of an Atom

Another name for Niels Bohr's atomic model.

Dalton's Atomic Theory

The theory that describes atoms as indivisible particles.

Joseph John Thomson's Theory

Also known as the Raisin Bun Model.

Ernest Rutherford

Physicist known for the Nuclear Model of an Atom.