Our Historical Journey

The Beginnings of Science and Chemistry

This thread of history takes us through Ancient Greece, through Northern Africa during what is called the Islamic Golden Age, and then into Europe as we follow the trail of alchemists which led to the development of several laws, then to pre-revolutionary France and the birth of modern Chemistry. Lastly, this part of our journey ends where it began with the idea of atoms, this time by John Dalton.

The Internal Structure of the Atom

This historical thread starts at Cambridge University in England around 1870. It begins with the construction of the Crookes Tube (named after the inventor William Crookes, who was the head of the Cavendish Laboratory at Cambridge). J.J. Thomson (the next director of the Cavendish) used Crookes’ tube to establish the existence of tiny negative particles, which he called electrons. Based on that discovery, Thomson created the first model of a (non-solid) atom and did further work determining the ratio between the charge of an electron and its mass. The next director of the Cavendish was Ernest Rutherford, who is credited with discovering the hard “nut” at the center of the atom (the nucleus) and with finding the proton. One of Rutherford’s proteges at the Cavendish, James Chadwick, discovered the neutron.

What electrons are and what they do

Once the existence of electrons had been established, it became clear that their behavior was a driving force in all of chemistry. Finding the charge on the electron was a complex and difficult task, but understanding the electron required the invention of a new physics. 

This path can be said to begin with the study of spectroscopy, the creation of equations that defined hydrogen spectroscopy, and the creation of quantum theory to explain those equations.

Even that isn't enough to really understand electrons. First we needed to understand the photoelectric effect, which was finally understood by a German patent clerk named Einstein (based on the work of Max Planck). This understanding was taken a step further by Louis de Broglie. The waters were muddied further by Werner Heisenberg’s Uncertainty Principle.

Erwin Schrödinger is credited with merging these seemingly disparate elements into an equation (and theory) of the behavior of electrons inside atoms.