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Radon

physical science Maturity 9-11 Next article →

Radon is a very rare chemical element. It is a noble gas, which means it does not like to react with other things. You cannot see, smell, or taste it. This makes it hard to notice without special tools.

Radon detector
Radon detector

Even though it is hard to find, it is very important to study. It is one of the densest gases in our atmosphere. In fact, it is about eight times denser than the air around us.

Radon spectrum
Radon spectrum

Radon is created through a natural process called decay. This happens when heavy elements like uranium and thorium break down. Radon is a step in these long decay chains. It comes from the decay of radium isotopes. The most stable version of radon has a half-life of 3.825 days. This means it stays around long enough to escape from rocks and soil. Eventually, the radon decays into other things called radon daughters. These finally turn into stable lead.

Decay chain(4n+2, Uranium series)
Decay chain(4n+2, Uranium series)

Scientists first discovered radon in 1899. Ernest Rutherford and Robert B. Owens found it at McGill University in Montreal. It was the fifth radioactive element ever found. At first, people called it "emanation." They thought different gases from radium, thorium, and actinium were separate things. Later, Sir William Ramsay and Robert Whytlaw-Gray realized these were part of the noble gas family. In 1923, the name radon was officially chosen for the most stable isotope.

Radon apparatus
Radon apparatus

Radon can be found in many places in nature. It often comes from uranium minerals in the ground. It can also be found in groundwater like hot springs. Sometimes, earthquakes can release radon into the air or water. It can even be released when permafrost thaws due to climate change. Because it is heavy, it often gathers in basements or crawlspaces.

Radon Concentration next to Uranium Mine
Radon Concentration next to Uranium Mine

We must be careful with radon because it can affect our health. Breathing high amounts of radon is linked to lung cancer. In the United States, the EPA says it causes 21,000 deaths every year. It is the second most common cause of lung cancer overall. However, it is the number one cause for people who have never smoked. Scientists use special tools like a cloud chamber to see its radiation.

Radon decay in a cloud chamber
Radon decay in a cloud chamber
US homes over recommended radon levels
US homes over recommended radon levels
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🖼️ Images & Media (13)
File:Radon spectrum.png
Radon spectrum.png
File:Radon decay in a cloud chamber.jpg
Radon decay in a cloud chamber.jpg
File:Decay chain(4n+2, Uranium series).svg
Decay chain(4n+2, Uranium series).svg
File:Radon apparatus.png
Radon apparatus.png
File:Lead210inairatjapan.png
Lead210inairatjapan.png
File:Radon Concentration next to Uranium Mine.PNG
Radon Concentration next to Uranium Mine.PNG
File:Radon Lognormal distribution.gif
Radon Lognormal distribution.gif
File:US homes over recommended radon levels.gif
US homes over recommended radon levels.gif
File:Stanowisko pomiaru radonu glebowego wf pw.jpg
Stanowisko pomiaru radonu glebowego wf pw.jpg
File:Radioactive Seeds (7845754328).jpg
Radioactive Seeds (7845754328).jpg
File:Uranium waste near Rifle, Colorado.jpg
Uranium waste near Rifle, Colorado.jpg
File:Radon detector.jpg
Radon detector.jpg

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