This date in 1852 was the birthdate of Sir William Ramsay, chemist who co-discovered radon. 10 things you might not know about Radon:
Radon is a noble gas with the symbol Rn and atomic number 86.
It is colourless and odourless.
Radon is created by the breakdown of radium and is a step in the decay chains of Uranium-238 and thorium-232.
There are 33 known isotopes of radon. Rn-226 is the most common of these. It has a half life of 3.825 days and is therefore the only naturally occurring isotope likely to be released into the atmosphere from the rocks where it is created. Even though it has a short half life, it’s not going to disappear any time soon because the elements that create it are abundant and have half-lives of at least several billion years.
Radon is present in the Earth's crust at an abundance of 4 x10-13 milligrams per kilogram.
Its melting point is202 K (−71 °C, −96 °F) and its boiling point is 211.5 K (−61.7 °C, −79.1 °F).
Although radon was observed as early as 1899 it was Ramsay and his colleague Robert Whytlaw-Gray who isolated it and determined its melting temperature and approximate density. In 1910, they determined that it was the heaviest known gas. They initially called the element niton but this changed to radon in 1923 after Radium, one of its sources.
It is a health hazard, even though as a noble gas it is inert and doesn’t easily form chemical compounds. The risk to health comes from the products of it breaking down, substances called "radon daughters" which can stick to things, like dust particles and the inside of a person’s lungs. Radon is the second leading cause of lung cancer and the leading cause of lung cancer in non-smokers.
Before people knew this, radon was often used as a medical treatment, including for cancer. In the early 20th century it was commonly used in spas with patients encouraged to bathe in it, inhale it and drink it. Water from springs with radon in them was bottled and sold, although by the time the customer bought it, thanks to radon’s short half life, it probably didn’t have any radon in it.
Radon is everywhere outdoors and in natural water sources but usually in such low concentrations it’s not a problem. If it accumulates in an enclosed space, such as a building or a mine, then it might be a problem. Every building contains radon but the levels are usually low. It is higher in areas where there’s a lot of granite. It’s possible to test for it and if the level is higher than desirable, the problem can be fixed with simple building works.
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