Radium emanation

From radium called niton at first, L. nitens, shining) The element was discovered in 1900 by Dorn, who called it radium emanation. In 1908 Ramsay and Gray, who named it niton, isolated the element and determined its density, finding it to be the heaviest known gas. It is essentially inert and occupies the last place in the zero group of gases in the Periodic Table. Since 1923, it has been called radon. 

Element 86, the final member of the group, is a short-lived, radioactive element, formerly known as radium-emanation or niton or, depending on which radioactive series it originates in (i.e. which isotope) as radon, thoron, or actinon. It was first isolated and studied in 1902 by E. Rutherford and F. Soddy and is now universally known as radon (from radium and the termination-on adopted for the noble gases Latin radius, ray). 

Ramsay and the other modern alchemists/chemists following his lead believed that they had found the proper energy sources for such syntheses of heavier elements in radium emanation—and eventually other sources of energy, including cathode rays and X-rays—to try to cause transmutations.20... 

While some contemporary alchemists such as Hunter, Emmens, Jollivet-Castelot, and Ayton had indeed tried to make gold, Ramsay s attempted transmutations led to a rush toward a different kind of treasure scientific immortality. Multiple chemists pursued the same kinds of experiments that Ramsay had, believing that they too had found positive results. They attempted to position themselves within the scientific world as the first to have proven artificial transmutation. Between 1907, when Ramsay announced his supposed copper transmutations in Nature, and 1914, when he abandoned his efforts, several significant chemists (including J. N. Collie, Hubert Patterson, E. C. C. Baly, Thomas Merton, Irvine Masson, and A. C. G. Egerton) all participated in experiments to use either radium emanation or cathode rays and X-rays to cause chemical transmutation. 

We must now more fully consider the radium emanation — a substance with more astounding properties than even the radium compounds themselves. By distilling off the emanation from some radium bromide, and measuring the quantities of heat given off by the emanation and the radium salt respectively, Professors Rutherford and Barnes proved that nearly three-fourths of the total amount of heat given out by a radium salt comes from the minute quantity of emanation that it contains. The amount of energy liberated as heat during fre decay of the emanation is enormous one cubic centimetre liberates about four... 

Sir William Ramsay, 1852-1916. Scottish chemist and physicist. Discoverer of the inert gases. Lord Rayleigh was a co-discoverer of argon, and M. W. Travis collaborated in the discovery of krypton, neon, and xenon. After F. E. Dorn had discovered radon, or radium emanation, Ramsay and Whidaw Gray determined its density and proved it to be the heaviest member of the argon family. 

May 14,1899 Aug. 16,1899 1899 1900 1900 Death of Nilson. Death of Bunsen. Debierne discovers actinium. Dorn discovers radon (radium emanation). Sir William Crookes discovers uranium Xj. 

Radium is chemically similar to barium it displays a characteristic optical spectrum its salts exhibit phosphorescence in the dark, a continual evolution of heat taking place sufficient in amount to raise the temperature of 100 times its own weight of water 1°C every hour and many remarkable physical and physiological changes have been produced. Radium shows radioactivity a million times greater than an equal weight of uranium and. unlike polonium, suffers no measurable loss of radioactivity over a short period of time (its half life is 1620 years). From solutions of radium salts, there is separable a radioactive gas radium emanation, radon, which is a chemically ineit gas similai to xenon and disintegrates with a half life of 3.82 days, with the simultaneous formation of another radioactive element, Radium A (polonium-218). 

RADON. [CAS 10043-92-2]. Chemical element symbol Rn, at. no. 86, at. wt. 222 (mass number of the most stable isotope), periodic table group 18 (inert gases), mp —71°C, bp —61.8°C. First ionization potential, 10.745 eV. Density 9.72 g/l O C, 760 torr), 7.5 x more dense than air. The gas has been liquefied at —65°C and solidified at —110°C. Radon was first isolated by Ramsay and Gray in 1908. Prior to acceptance of the present designation, radon was called niton or radium emanation. See also Radioactivity. 

Since the mid-1980s, there has been a growing concern among some pollution experts with the topic of indoor air pollution, and as a major part of this problem, the presence in homes and other structures of ionizing radiation in the form of radon gas. It is beginning to appear that radon s earlier designation as radium emanation was not inappropriate. Most health... 

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