Lavoisier’s Chemistry: 1750–1870

“In nature nothing is created, nothing is lost, everything is transformed,” is the famous quote attributed to Antoine Lavoisier. At the time of the Scientific Revolution, astronomy and physics stood alone as sciences. Alchemy was a mix of the mystical and the pragmatic (sometimes practiced by the same scientists who were advancing physics). It’s a fair question whether chemistry arose out of alchemy or was a replacement for it, but in any case, it evolved about a century after the Scientific Revolution. Looking back to alchemy’s fascination with conversion of metals, chemistry identified new elements, especially hydrogen and oxygen. Lavoisier was a prime mover. In fact, he has often been called the first chemist. His importance is as much with the fact that his methodology placed chemistry on a quantitative basis as with his conclusions. This marked the transition from alchemy to science. Lavoisier’s Revolution has a poignant double meaning, because Lavoisier was guillotined in the French Revolution. “It took an instant to cut off his head, it may take a hundred years before there is another like it,” was a sad contemporary comment. In the next century, looking forward to physics, chemistry identified atoms, as first conceived by John Dalton, and then defined the atomic properties of elements, as characterized by Mendeleev and others.