Nobelt guld smält upplöst

On the day the Nazis came to Copenhagen, a Hungarian chemist named Georgy de Hevesy (he would one day win a Nobel of his own) was working in Bohr's lab. He wrote later, \"I suggested that we should bury the medal(s),\" but Bohr thought no, the Germans would dig up the grounds, the garden, search everywhere in the building. Too dangerous.

So Hevesy's thoughts turned to chemistry. Maybe he could make the medals disappear. He took the first one, he says, and \"I decided to dissolve it. While the invading forces marched in the streets of Copenhagen, I was busy dissolving Laue's and also James Franck's medals.\"

This was not an obvious solution, since gold is a very stable element, doesn't tarnish, doesn't mix, and doesn't dissolve in anything -- except for one particular chemical emulsifier, called \"aqua regia,\" a mixture of three parts hydrochloric acid and one part nitric acid.