FREMY, EDMOND. - TOWARDS ISOLATION OF FLUORINE FREMY'S SALT.

Recherches sur les Fluorures. Premier Mémoire.

Paris, Victor Masson, 1856. No wrappers. Extracted from: "Annales de Chimie et de Physique", 3e Series - Tome 47. Pp. 5-50. Textillustr. With titlepage to vol. 47. Some scattered brownspots.

First appearance of Fremy's importent paper on the isolation of fluorine, a historic paper in electro-chemistry. The existence of the element fluorine had been well known for many years (since 1813, Davy), but all attempts to isolate it had failed and some experimenters had died in the attempt.

"The history of fluorine is a tragic record. Marggraf described hydrofluoric acid in 1768, and Scheele studied it three years later. Lavoisier..., thought that all acids contain oxygen, but Davy showed that this one does not. Ampere suggested to Davy that hydrofluoric acid must be composed of hydrogen and an unknown element. Poul Schutzenberger expressed the belief that this unknown substance, fluorine, would be found to be the most active of all elements, and correctly predicted some of its properties. Ti is this extreme activity of the element that made its liberation such a difficult and dangerous task and brought agony and death to some of the pioneer investigators."(Weeks p. 266-67).

"An important step was made by Frémy, Moissan’s first mentor, when he succeeded in preparing pure, anhydrous HF and also KHF2, so-called Frémy’s salt, expressed "KFl.HFl" using the notations of that time. Frémy had come very close to finding the solution by electrolysing anhydrous HF, molten calcium fluoride or potassium fluoride, but he seemed not to have had the idea of replacing these compounds by KHF2, perhaps because of the high melting point of the compound, TF = 293°C, which would have led to insurmountable technical difficulties."

Weeks "Discovery of teh Elements", p. 266 ff.

Order-nr.: 45677