Percy, Marguerite

The isolation and identification of 4 radioactive elements in minute amounts took place at the turn of the century, and in each case the insight provided by the periodic classification into the predicted chemical properties of these elements proved invaluable. Marie Curie identified polonium in 1898 and, later in the same year working with Pierre Curie, isolated radium. Actinium followed in 1899 (A. Debierne) and the heaviest noble gas, radon, in 1900 (F. E. Dorn). Details will be found in later chapters which also recount the discoveries made in the present century of protactinium (O. Hahn and Lise Meitner, 1917), hafnium (D. Coster and G. von Hevesey, 1923), rhenium (W. Noddack, Ida Tacke and O. Berg, 1925), technetium (C. Perrier and E. Segre, 1937), francium (Marguerite Percy, 1939) and promethium (J. A. Marinsky, L. E. Glendenin and C. D. Coryell, 1945). 

Francium - the atomic number is 87 and the chemical symbol is Fr. The name derives from the country France , where the French physicist Marguerite Percy from the Curie Institute in Paris, France discovered it in 1939 in the alpha particle decay of actinium, Ac => He => Fr, which was known as actinium-K and has a half-life of 22 minutes. An earlier claim of discovery in 1930 with the element name Virginium was determined to be incorrect. A similar claim for discovery of the element with atomic number 87 and named moldavium was also determined to be incorrect. The longest half-life associated with this unstable element is 22 minute Fr. 

Element 87 was isolated by Marguerite Percy, who was studying the radioactive decay of the element actinium. Radioactive elements like actinium break apart spontaneously, giving off energy and particles. This process results in the formation of new elements. 

Percy s Legacy Marguerite Percy made important discoveries during an era when few women held prominent roles in the sciences. She was interested in science even as a small child. However, her father died early on, and there was no money for Percy to attend a university. Instead, she found a job at the Radium Institute in Paris. The Radium Institute had been founded by Marie Curie (1867-1934) and her husband, Pierre Curie (1859-1906), to study radioactive materials. 

French chemist Marguerite Percy discovers francium. 

In 1939, an element subsequently named francium, number 87, was discovered in Paris by Marguerite Percy, and in 1940 Segre discovered astatine, element 85. The final piece of the jigsaw puzzle, element 61, promethium, was finally obtained as a byproduct in a nuclear reaction. The discoverers on this occasion were Jacob Marinsky, Lawrence Glendenin, and Charles Coryell. ... 

Hafnium Hevesy, Himgary, 1923 87 Francium Marguerite Percy, 1939... 

The elements in group 1 are hydrogen and the alkali metals lithium li, sodium Na, potassium K, rubidium Rb, cesium Cs and francium Fr. The last one, francium, was discovered in 1939 by Marguerite Percy in Paris. It will be described in Chapter 52 The Radioactive Elements. The others wiU be treated in this and the following two chapters. 

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