Your favorite chemistry story

[SpongeBob SquareChemist]

I have a few. I love Kekule's account of how benzene's structure came to him in a dream. Here's what he said.

"I was sitting writing on my textbook, but the work did not progress; my thoughts were elsewhere. I turned my chair to the fire and dozed. Again the atoms were gamboling before my eyes. This time the smaller groups kept modestly in the background. My mental eye, rendered more acute by the repeated visions of the kind, could now distinguish larger structures of manifold conformation; long rows sometimes more closely fitted together all twining and twisting in snake-like motion. But look! What was that? One of the snakes had seized hold of its own tail, and the form whirled mockingly before my eyes. As if by a flash of lightning I awoke; and this time also I spent the rest of the night in working out the consequences of the hypothesis."

Benzene - a snake biting its own tail.

Attachment below by http://commons.wikimedia.org/wiki/User:Vladsinger

[jeffy]

Debunking Caloric

Caloric was a weightless fluid held inside substances. It could be transferred from one substance to another, so that the one warmed the other up. Two pieces of wood rubbed together would heat up because grains of wood would be rubbed off, releasing caloric.

Near the end of the 1700's Benjamin Thompson noticed a lot of heat being released during the boring of a cannon. According to the caloric theory this was because, as fragments of metal flew off as drilling took place, caloric was released.

Thompson noticed that when the drills got blunter more heat was released. This was the opposite of what caloric theory said should happen. He calculated the amount of caloric released and showed that if it could be put back into the cannon, it would melt. So there could never have been that much caloric in the cannon ever.

It wasn't until almost 50 years later that James Joule published his "Mechanical Equivalent of Heat" paper finally beginning our understanding of heat.