Molecular Monday: The Discovery of Lithium

Welcome back to another edition of Molecular Mondays, a special biweekly series here on Planet Pailly combining two of my least favorite things: chemistry and Mondays.

My current Sci-Fi work in progress is starting to turn into a bigger project than I originally anticipated, which means I need to learn more about lithium: the chemical element which I’ve unwisely scattered all over a certain alien moon.

Over the years, I’ve found that one of the best ways to learn about science (at least for me) is to take a historical approach. With that in mind, today I’d like to talk a little about the moment in history when lithium was first discovered.

It was 1817. Sweedish chemist Johan August Arfwedson was working in the laboratory of Jon Jakob Berzelius, on of the great “fathers of modern chemistry.”

Apparently it was common practice for chemists at that time (and also for chemists today) to light things on fire in order to see what color flames they’d get. Because different materials burn in different colors, the colors can tell you a great deal about what material you’re actually working with. Today this is known as a flame test.

Arfwedson was flame testing a kind of rock called petalite. When burned, petalite produced an intense crimson flame, like this:

Now when Arfwedson saw those bright crimson flames, he did not immediately conclude that he’d discovered a new element. Instead, he did what any good scientist would do: he thought up possible explanations for this crimson color and then systematically tested each possibility, ruling them out one by one.

In the end, Arfwedson was left with only one possibility: petalite must contain a previously unknown alkali metal. Arfwedson named this alkali metal lithium, after the Greek word for stone. “This name,” Berzelius, Arfwedson’s mentor, would later write, “recalls that it was discovered in the mineral kingdom, whereas the two others [sodium and potassium were the only other known alkali metals at the time] have their origin in the vegetable kingdom.”

At this point, you might be wondering what any of this has to do with my story. I’m kind of wondering that myself. Umm… I’ll get back to you about that. In the meantime, there are lots of other cool flame test videos to watch on YouTube.

Sources

Lithium from the Royal Society of Chemistry

Lithium from Elementymology & Elements Multidict

Alkali Metal from the Encyclopedia Britannica