Nobel Prize winning physicist Richard Feynman once said:
"If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generation of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis that all things are made of atoms -- little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another. In that one sentence, you will see, there is an enormous amount of information about the world, if just a little imagination and thinking are applied."
Atoms are the fundamental building blocks of everything tangible around us - be it human beings or pebbles. We are all made of atoms. And since each of those atoms was once upon a time created in a star, we are literally stardust! The remnants of super novae from ages past.
Last week, we were talking about isotopes - the variations in atomic nuclei as a result of different numbers of neutrons. For example, 50 protons in a nucleus makes an atom "tin" and only 50 protons but the number of neutrons ranges from 62 to 74. Tin exhibits 10 stable isotopes.
However, isotopes are only a recent addition in our understanding of atoms. One could make the argument the history of modern civilization is intimately linked with atoms.
From pre-history to now, human beings have manipulated atoms to our own ends. We have taken elements, such as tin, and separated them to make metals. We have combined them with other atoms to make alloys such as brass and bronze. And we combined them with other elements to make ionic compounds, such as stannous fluoride (tin II fluoride).
Much of the history of the world has depended upon the understanding of atoms - except for the longest time no one knew anything about atoms themselves.
But such processes as glassmaking, which began in the Middle East over 5,000 years ago, depend on being able to combine silica and soda in an extremely hot kiln. Making pottery pre-dates glass by several thousand years or more. It involves taking aluminosilicates and other materials and driving the water from their lattices to form new durable structures.
Some of the earliest of human inventions depended upon biochemistry. For example, making wine requires the chemical reactions occurring in yeast to convert sugar to ethanol and carbon dioxide. It is a natural process which will occur in any fruit under anaerobic conditions but perfecting the process was a matter of scientific inquiry. Similarly, making beer, cheese, and leavened bread all depend on reliably being able to take advantage of naturally occurring chemical processes which allows us to manipulate atoms in very specific ways.
Egyptian craftsmen were able to make fake gems to adorn the sarcophagi of the Pharaohs. Roman tradesmen used lead salts to sweeten their wine. Chinese scholars invented gun powder as an elixir capable of granting eternal life. (The fact it also goes bang was just an added bonus.)
World history moved along with the invention of better ways to manipulate atoms. Whether in art, where cobalt smalt replaced lapis lazuli in making the blue colour for skies, or metallurgy, where steel replaced iron making for stronger lighter armor, we have advanced as our understanding of atoms has grown.
Prior to the 1700s, no one really knew what lay underneath all of this science and technology. Spirits? Mixtures of the four or five essential elements? Tiny pieces of the all-malleable aether?
In the late 1700s, scientists such as Antoine Lavoisier and Joseph Priestley began to suspect there might exist underlying principles. Individual compounds - such as carbon monoxide and carbon dioxide - were discrete combinations of elements. Carbon and oxygen could have a 1-to-1 ratio or a 1-to-2 ratio but not somewhere in between. This implied discrete particles giving rise to these chemical combinations.
By 1808, these chemical ideas were sufficiently well developed that John Dalton was able to synthesize them into an atomic hypothesis. Much of the 19th century science explored atoms and exploded myths such as the notion atoms and compounds in living organisms were somehow different from atoms and compounds in non-living organisms.
By 1858, the ideas around atoms were coming together and 150 years ago, Dmitri Mendeleev was formulating the known elements into the periodic table. It wasn't until the early 1900s that the work of Henri Becquerel, J.J. Thomson, Pierre and Marie Curie, and Ernst Rutherford built the foundation which allowed for the development of the atomic hypothesis. Even then, it took Niels Bohr to explain why the atom is the way it is - little particles in perpetual motion.
Yes, understanding atoms, isotopes, chemical bonds, and atomic interactions is the basis for our modern world. After all, atoms make up everything.
