There are 37 known isotopes of radon (86 Rn), from 195 Rn to 231 Rn; all are radioactive.The most stable isotope is 222 Rn with a half-life of 3.823 days, which decays into 218 Po. Radon gas is colorless, but it exudes a brilliant yellow phosphorescence at temperatures below its freezing point. Decades ago, radium salts were mixed into paints to make them glow in the dark. Once radon was deemed a health risk, radon was pulled from all consumer products. Radon has an atomic number of 86; The atomic symbol for radon is Rn. Element Radon (Rn), Group 18, Atomic Number 86, p-block, Mass 222. Sources, facts, uses.

• Rn Atomic Mass
• What Period Is Radon In
• Radon Periodic Number

Radon

History

The name was derived from radium; called niton at first, from the Latin word nitens meaning 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.

Isotopes

Thirty-nine isotopes are known. Radon-222 is the most common. It has a half-life of 3.823 days and is an alpha emitter. It is estimated that every square mile of soil to a depth of 6 inches contains about 1 g of radium, which releases radon in tiny amounts into the atmosphere. Radon gas can collect in buildings, creating a health risk. The Environmental Protection Agency estimates that responsible for an estimated 20,000 lung cancer deaths each year. More on radon and health. Radon is present in some spring waters, such as those at Hot Springs, Arkansas.

Properties

Radon is present in the atomosphere at very low concentrations. See Wikipedia for discussion of concentration. At ordinary temperatures radon is a colorless gas; when cooled below the freezing point, radon exhibits a brilliant phosphorescence which becomes yellow as the temperature is lowered and orange-red at the temperature of liquid air. Hindi movie jai ho full movie download. It has been reported that fluorine reacts with radon, forming a fluoride. Radon clathrates have also been reported.

Uses

Radon is still produced for therapeutic use by a few hospitals by pumping it from a radium source and sealing it in minute tubes, called seeds or needles, for application to patient. This practice has been largely discontinued as hospitals can get the seeds directly from suppliers, who make up the seeds with the desired activity for the day of use.

Handling

Care must be taken in handling radon, as with other radioactive materials. The main hazard is from inhalation of the element and its solid daughters which are collected on dust in the air. Good ventilation should be provided where radium, thorium, or actinium is stored to prevent build-up of the element. Radon build-up is a health consideration in uranium mines. Recently radon build-up in homes has been a concern. Many deaths from lung cancer are caused by radon exposure. In the U.S. it is recommended that remedial action be taken if the air in homes exceeds 4 pCi/l.

Radon is a radioactive gas that forms naturally when uranium, thorium, or radium, which are radioactive metals break down in rocks, soil and groundwater. People can be exposed to radon primarily from breathing radon in air that comes through cracks and gaps in buildings and homes. Because radon comes naturally from the earth, people are always exposed to it.

Rn Atomic Mass

See also:

• Radiation Protection Division: Radon - https://www.epa.gov/radiation/radionuclide-basics-radon
• EPA's Integrated Risk Information System profile on Radon 222 [CASRN 14859-67-7] is located at: https://cfpub.epa.gov/ncea/iris/iris_documents/documents/subst/0275_summary.pdf

What Period Is Radon In

Radon Periodic Number

Read more about Radon at www.epa.gov/radon