the atomic theories

Dalton's Atomic Theory

Theory stating that elements are made of indivisible atoms, identical in mass and properties, and react through rearrangement.

Plum Pudding Model

J.J. Thomson's model of the atom depicting it as a uniform sphere of positive charge with scattered electrons.

Gold Foil Experiment

An experiment conducted by Rutherford that led to the discovery of the atomic nucleus.

Nuclear Model

Rutherford's model stating that atoms have a small, dense nucleus with orbiting electrons.

Bohr Model

Refinement of the atomic model that introduced quantized orbits for electrons.

Ground State

The n=1 orbit of an electron, where it has the lowest energy and greatest stability.

Excited States

States of electrons in orbits n=2 and higher, where they have more energy but less stability.

Energy Absorption in Electrons

When an electron absorbs energy, it moves to a higher orbit.

Energy Release in Electrons

When an electron loses energy, it transitions to a lower orbit.

Atomic Structure

Composed of protons, neutrons, and electrons, where neutrons and protons are found in the nucleus.

Electron

A negatively charged subatomic particle discovered by J.J. Thomson.

Neutron

A neutral subatomic particle discovered by James Chadwick, found in the nucleus.

Proton

A positively charged subatomic particle discovered by Rutherford located in the nucleus of an atom.