Difference between revisions of "Radon"
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Latest revision as of 18:59, 23 December 2021
| General properties | |||||
|---|---|---|---|---|---|
| Name, symbol | Radon, Rn | ||||
| Appearance | Colorless gas | ||||
| Radon in the periodic table | |||||
| |||||
| Atomic number | 86 | ||||
| Standard atomic weight (Ar) | 222 | ||||
| Group, block | 18 (noble gases); p-block | ||||
| Period | period 6 | ||||
| Electron configuration | [Xe] 4f14 5d10 6s2 6p6 | ||||
per shell | 2, 8, 18, 32, 18, 8 | ||||
| Physical properties | |||||
| Colorless | |||||
| Phase | Gas | ||||
| Melting point | 202 K (−71 °C, −96 °F) | ||||
| Boiling point | 211.5 K (−61.7 °C, −79.1 °F) | ||||
| Density at (0 °C and 101.325 kPa) | 9.73 g/L | ||||
| when liquid, at | 4.4 g/cm3 | ||||
| Triple point | 377 K, 6.28 kPa | ||||
| Heat of fusion | 3.247 kJ/mol | ||||
| Heat of | 18.10 kJ/mol | ||||
| Molar heat capacity | 5R/2 = 20.786 J/(mol·K) | ||||
| pressure | |||||
| Atomic properties | |||||
| Oxidation states | 0, +2, +6 | ||||
| Electronegativity | Pauling scale: 2.2 | ||||
| energies | 1st: 1037 kJ/mol | ||||
| Covalent radius | 150 pm | ||||
| Van der Waals radius | 220 pm | ||||
| Miscellanea | |||||
| Crystal structure | | ||||
| Thermal conductivity | 3.61×10−3 W/(m·K) | ||||
| Magnetic ordering | Non-magnetic | ||||
| CAS Registry Number | 10043-92-2 | ||||
| History | |||||
| Discovery | Ernest Rutherford and Robert B. Owen (1899) | ||||
| First isolation | William Ramsay and Robert Whytlaw-Gray (1910) | ||||
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas. Radon occurs naturally in minute quantities as the immediate decay product of radium, which in turn is an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into various short-lived radioactive elements and finally into lead.
Contents
Properties
Chemical
It is inert to most common chemical reactions, such as combustion, because the outer valence shell contains eight electrons. This produces a stable, minimum energy configuration in which the outer electrons are tightly bound.
Radon can be oxidized by powerful oxidizing agents such as fluorine, thus forming radon difluoride (RnF2). It decomposes back to its elements at a temperature of above 250 °C, and it hydrolyzes in contact with water to radon gas and hydrogen fluoride.
An oxide of radon, radon trioxide (RnO3) has been confirmed.
Due to the short half-life of radon, its chemistry hasn't been thoroughly studied.
Physical
Radon is a radioactive, colorless, odorless, tasteless noble gas. Due to its short half-life, a concentrated amount of radon may glow on its own because of the intense radiation it produces. If condensed, it becomes phosphorescent yellow, deepening to glowing red as it is chilled below its freezing point.
At standard temperature and pressure, it forms a monatomic gas with a density of 9.73 kg/m3, about 8 times the density of the Earth's atmosphere at sea level. It is sparingly soluble in water, but more soluble than lighter noble gases. It is appreciably more soluble in organic liquids than in water.
Availability
Radon can be extracted from natural uranium ores.
Isolation
To isolate significant amounts of radon, one would need a large amount of uranium or thorium ore. In areas with large geological deposits, the air from the basement of the buildings is constantly pumped out to prevent a dangerous build-up of radon gas. In theory, one could obtain small amounts of radon gas from this process, albeit due to its short half-life, it must be used quickly.
Vials containing large concentrations of radium metal or radium compounds will release radon gas.
Projects
- Study radioactivity
- Element collecting (placing a piece of natural uranium ore near a radon detector is a convenient setup)
Handling
Safety
Radon is radioactive and exposure may increase the risk of cancer, specifically lung cancer. People who live in areas where radon is present due to geology, are at a more significant risk of developing lung illnesses. The basement of houses in such areas need to be constantly vented to prevent a dangerous build-up of radon gas.
Storage
Radon cannot and should not be stored.
Disposal
Should be vented in the atmosphere, where it will slowly decay into less harmful products.
