Introduction
The Atomic Theory has been a subject of study for centuries, and ancient Greek philosophers were some of the first to delve into these concepts. Their analogies, particularly the "legos" analogy, laid the foundation for how we understand atoms today.
Greek Philosophers' Analogy Legos List
Around 2000 years ago, Greek philosophers such as Democritus and Leucippus began musing on the nature of the world and concluded that all things are made up of tiny, uncuttable particles known as "atomos."
John Dalton: The Solid Sphere
Fast forward to the 19th century, and English chemist John Dalton created his atomic theory based on three laws. His theory claimed that all matter is composed of indivisible, tiny particles named atoms, and each element's atoms are identical.
Dalton's theory also stated that compounds and molecules form when two or more atoms chemically join. This concept is analogous to "billiard balls" where atoms combine in a fixed whole number ratio.
J.J. Thomson's Cathode Ray Tubes Experiment
In 1897, J.J. Thomson discovered electrons using cathode ray tubes. His experiment with the tubes revealed that atoms contain negatively charged particles smaller than an atom, leading him to conclude that atoms must contain another particle with a more significant mass and opposite charge, thus proposing the plum pudding model.
Ernest Rutherford's Gold Foil Experiment
Ernest Rutherford's famous gold foil experiment took place in the early 20th century. By observing alpha radiations passing through gold foil, he concluded that atoms contain empty spaces and a small, dense nucleus with protons and electrons orbiting around it.
James Chadwick's Discovery of Neutrons
In the early 1900s, James Chadwick discovered neutrons, the third subatomic particles in atoms. Neutrons have no charge but contribute to the extra mass found in an atom, aiding in explaining atomic structure.
As we can see, the evolution of atomic theory spans centuries and involves various key figures and experiments, each contributing to how we understand the composition and structure of atoms today.
