Evolution of atomic models

 Evolution of atomic models ✍️

Dalton (1803) : John Dalton proposed that atoms are tiny, solid, indivisible spheres - the simplest form of matter. His model is often called the "billiard ball model."

Thomson (1904) : J.J. Thomson discovered the electron and suggested the "plum pudding model," where atoms are spheres of positive charge with negatively charged electrons embedded like plums in a pudding.

Rutherford (1911) : Ernest Rutherford’s famous gold foil experiment led to the nuclear model: atoms are mostly empty space, with a small, dense, positively charged nucleus at the center and electrons orbiting around it.

Bohr (1913) : Niels Bohr refined Rutherford’s model by introducing quantized energy levels: electrons orbit the nucleus in fixed paths (like planets around the sun), and can jump between these levels.

Schrödinger (1926) : Erwin Schrödinger developed the modern "electron cloud model," using quantum mechanics. Instead of fixed orbits, electrons exist in probabilistic "clouds" where they are likely to be found.