“Does a connection or relationship exist between the reactivity of a metal and when it was discovered?” By: Nicholas Roberto

Periodic Table of Elements

Reactivity Series (Not Metals)

Potassium (K) Potassium is a highly reactive metal. It is the seventh most abundant metal on earth. It cannot maintain it’s natural form due to its highly reactive nature. In its free form, potassium is a very soft silver-white metal. It needs to be contained in mineral oil to prevent it’s disintegration. In the eighteenth century, people were familiar with potash since they used it for cleaning purposes. Potash is a compound made from wood ashes. In 1807, Humphrey Davy a British chemist started working on isolating elements from their compounds. He first made water solutions of potash and soda ash and then passed electric current through it. This method did not yield any results, as the elements, soon after their isolation from the compounds, reacted with the water. Hence, Davy could not see any free element as such. Soon after that, Davy decided to extract the water (h 2 o) from what he had found. He passed electric current through the molten solution of potash, which led to the emergence of tiny droplets of the metal. He named it Potassium, from potash. This process was achieved on October 6, 1807 and potassium was the first metal isolated by electrolysis. A few days later he discovered sodium, using the same method.

Sodium (Na) Sodium chloride, known as salt, has been familiar to the world since antiquity. The first time sodium was used, or discovered was when the Egyptians used it for their foods. Metallic sodium was first isolated by Humphrey Davy in 1807 using the electrolysis of solid sodium hydroxide At that time, sodium hydroxide was considered an elementary substance and was called fixed alkalis.

Magnesium(Mg) Magnesium has an interesting history. In 1618 a farmer at Epsom in England tried to give his cows water from a well. They refused to drink. The water has specific taste - bitter taste. That water was with health features. The popularity of Epsom salts spread which is used today to treat minor skin abrasions. They were identity to be magnesium sulphate - MgSO 4. In 1755 was recognized magnesium as an element. First isolation was done by Davy in 1808 who find a mixture of magnesia (magnesium oxide, MgO) and mercuric oxide (HgO).

Calcium (Ca) The metal has a silvery color, is rather hard, and is prepared by electrolysis of the fused chloride to which calcium fluoride is added to lower the melting point. Calcium is a metallic element, fifth in abundance in the earth's crust, of which if forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells. Never found in nature uncombined, it occurs abundantly as limestone, gypsum, and fluorite. Apatite is the fluorophosphate or chlorophosphate of calcium. Though lime was prepared by the Romans in the first century under the name calx, the metal was not discovered until After learning that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, Davy was able to isolate the impure metal

Aluminium Aluminum is the third most abundant element of the Earth’s crust, behind that of oxygen and silicon. Of the metallic elements, it is the most abundant, 7.3% by mass of the total crust. Due to Aluminum’s high affinity to bind with oxygen, it is not found in naturally occurring in its elemental state, but only in combined forms such as oxides or silicates. The metal originally obtained its name from the Latin word for alum, alumen. The name alumina was proposed by L. B. G. de Moreveau, in 1761 for the base in alum, which was positively shown in 1787 to be the oxide of a yet to be discovered metal. Finally, in 1807, Sir Humphrey Davy proposed that this still unknown metal be referred to as aluminum. This was then altered further to that of aluminium so to agree with the "ium" spelling that ended most of the elements. This is the spelling that is generally used throughout the world. That is, until the American Chemical Society in 1925 officially reverted the spelling back to aluminum, which is how it is normally spelled in the United States.

“Does a connection or relationship exist between the reactivity of a metal and when it was discovered?” Yes, there is a connection. The older the metal is the easier it is to extract.

Bibliography "History of Potassium." Buzzle Web Portal: Intelligent Life on the Web. Web. 10 Nov potassium.html "Sodium: History." Nautilus Home Page. Web. 14 Nov HistoryOfAluminum - History. Web. 22 Nov "ELEMENT: CALCIUM." RADIOCHEMISTRY SOCIETY - Specialized Courses in Radiochemistry. Web. 22 Nov "Forbidden." The Worlds of David Darling. Web. 22 Nov