Scandium History

Dmitri Mendeleev used his periodic law, in 1869, to predict the existence and some properties of three unknown elements including one he called ekaboron .

Lars Fredrick Nilson and his team, apparently unaware of that prediction in the spring of 1879, were looking for rare earth metals; using spectrum analysis he found a new element within the minerals euxenite and gadolinite. He named it Scandium, from the Latin Scandia meaning "Scandinavia", and by way of isolating the element he processed 10 kilograms of euxenite with other rare-earth residues, obtaining about 2 grams of very pure scandium oxide (Sc2O3).

Per Teodor Cleve concluded that scandium corresponded well to the hoped-for ekaboron, and notified Mendeleev of this in August.

Fischer, Brunger, and Grienelaus prepared metallic scandium for the first time in 1937, by electrolysis of a eutectic melt of potassium, lithium, and scandium chlorides at 700 to 800° C Tungsten wire in a pool of liquid zinc were the electrodes in a graphite crucible. The first pound of 99% pure scandium metal wasn't produced until 1960.

Potassium History

Potassium was discovered in 1807 by Sir Humphrey Davy, who derived it from caustic potash (KOH). Potassium was the first metal that was isolated by electrolysis.

Potassium was not known in Roman times, and its names are not Classical Latin.
The name kalium was taken from the word "alkali", which came from Arabic al qalīy = "the calcined ashes".
The name potassium was made from the word "potash", which is English, and originally meant an alkali extracted in a pot from the ash of burnt wood or tree leaves.



Potassium makes up about 2.40% of the weight of the Earth's crust and is the seventh most abundant element in it. As it is very electropositive, potassium metal is difficult to obtain from its minerals.

Potassium salts such as carnallite, langbeinite, polyhalite, and sylvite are found in ancient lake and sea beds. These minerals form extensive deposits in these environments, making extracting potassium and its salts more economical. The principal source of potassium, potash, is mined in California, Germany, New Mexico, Utah, and in other places around the world. 3000 feet below the surface of Saskatchewan are large deposits of potash which are important sources of this element and its salts, with several large mines in operation since the 1960's. Saskatchewan pioneered the use of freezing of wet sands (the Blairmore formation) in order to drive mine shafts through them. See Potash Corporation of Saskatchewan. The oceans are another source of potassium, but the quantity present in a given volume of seawater is relatively low compared to sodium.

Potassium can be isolated through electrolysis of its hydroxide in a process that has changed little since Davy. Thermal methods also are employed in potassium production, using potassium chloride. Potassium is almost never found unbound in nature. However, in living organisms K+ ions are important in the physiology of excitable cells.