Radon is a chemical element in the periodic table that has the symbol Rn and atomic number 86. Radon is also included in the group of noble and radioactive gas. Radon is formed from radium decomposition. Radon is also the heaviest gas and harmful to health. Rn-222 has a half-life of 3.8 days and is used in radiotherapy.(Read Examples of Monoatomic and Diatomic Gases)
The radon name comes from radium. Radon was discovered in 1900 by Friedrich Ernst Dorn, who wrought it as radium emission. In 1908 William Ramsay and Robert Whytlaw-Gray, who called it the niton (from the nitens latin language “shimmering” Nt symbol), isolated it, determined its density and they discovered that Radon was the heaviest gas of the time (until this day) . Since 1923 this element 86 is called Radon. Here’s the explanation about commercial and industrial uses of radon.
Radon is not easy to react chemically, but radioactive, radon is also a natural gas (the heaviest gas compound is tungsten hexafloride, WF6). At room temperature and pressure, the radon is colorless but when cooled to freeze, radon will be yellow, while the liquid radon is orange red. (Read Monoatomic Gas Definition)
Radon gas accumulation naturally in the earth’s atmosphere occurs very slowly so that water that touches free air continues to lose Radon due to the process of “Volatilization. Ground water has a higher content of Radon than surface water.
On average, there is one radon molecule in 1 x 1021 air molecule. Radon can be found in some springs and hot springs. Misasa Town, Japan, is famous for its water-rich springs that produce radon. Radon is freed from the soil naturally, especially in the landed areas of Granite.
On average, there is one radon molecule in 1 x 1021 air molecule. Radon is freed from the soil naturally, especially in the landed areas of Granite. In the earth, naturally, there is natural radiation, which has existed since the earth’s formation. In accordance with the theory of the formation of the earth, the heavy element will be in the interior of the earth, while the light element will be on the outside.
Radon gas is potentially out of the bowels of the earth, due to various geological or man-made events. Radon is the result of decay of U-238, and further decays by emitting alpha particles and forming unstable isotopes of Polonium-218 (solids) and further into Po-214 until finally forming stable isotope Pb-206 (Bud, 2009) (Read Examples of Gas Turning into Solid)
Radon may also be able to gather in dungeons and dwellings (but this also depends on how the house is treated and ventilated) The EU determines that the safe limit of radon content is 400 Bq / meter3 for the old house, and 200 Bq / m3 for the new house .
The American Environmental Protection Agency advises to take immediate action for all homes with Radon concentrations exceeding 148 Bq / m3 (measured as 4 pCi / L). Almost a house every 15 in the U.S. have high levels of radon according to statistics (U.S. Surgeon General) and EPA reserve for all homes to be tested for radon. Since 1985 in America, millions of homes have been tested for its radon content.
The characteristics of Radon :
- Atom Number: 86
- Period: 6
- Blocks: p
- Appearance: Colorless
- Atomic Mass: (222) g / mol
- Electron configuration: [Xe] 4f14 5d10 6s2 6p6
- Number of electrons in each skin: 2 8 18 32 18 8
- Valence electrons: 8
- Crystal Structure: Cube
- Electronegativity: 2.2 (Pauling scale)
- Energy Ionization: 1037 kJ · mol-1
- Atomic radius: 120 pm
- Covalent: 145 pm
- Phase: Gas
- Mass Type: (0 ° C, 101,325 kPa) 5.894 g / L
- Melting Point: 202 K (-71.15 ° C, -96 ° F)
- Boiling Point: 211.3 K (-61.85 ° C, -79.1 ° F)
- Heat Capacity: (25 ° C) 20.786 J · mol-1 · K-1
- Processing of Radon
- Radon is derived from Radium disintegration
- 88Ra → 86Rn + 2He
The Commercial and Industrial Uses of Radon
- Radon is sometimes used by some hospitals for therapeutic uses. The radon is obtained by pumping from the Radium source and stored in a small tube called ” seed ” or ” needle ”. Radon is rarely used again but, given that hospitals can now get the seeds of ” suppliers ” that produce the seeds with the desired decay rate. usually cobalt and cesium are used which are resistant for several years, so it is more practical in terms of logistics. (Read also : Helium Uses in Medicine)
- Because of its fairly rapid decay, radon is also used in hydrological investigations that examine the interactions between underground water, creeks and rivers. Increased radon in creeks or rivers is an important clue that there is an underground water source.
- Radon can also act as an earthquake warning system or earthquake disaster mitigation efforts, because when the earth plate moves radon levels will change so it can be known if there is an earthquake of radon levels change.
There is an example of the use of radon that has been conducted by a number of researchers at the National Aviation Institute (LAPAN). The radon gas that is present in the soil is continuously monitored for two consecutive years.
This research has aims to analyze the variations of radon gas and earthquake activity as well as the emergence of local earthquake precursors that occur in the Opak Fault lane. The results showed an increase in radon gas emissions correlated with an increase in the frequency of earthquake events.
- Radon gas is radioactive so it is widely used in radiation therapy for cancer patients by utilizing the resulting light. However, if radon sucked in sufficient quantities will cause lung cancer.
- It is also used in geological research and tracks air masses. (Read Harmful Chemicals in Air Pollution)
Radiation : One thing to notice of radon gas
Radiation derived from radon gas (Rn-222) is the main source of radiation we receive daily. This happens because Rn-222 can join the air we breathe. Then, the radon gas that emits alpha radiation can irradiate the lungs thus increasing the risk of getting cancer.
If the radon gas comes out of the ground, the radon gas will be dispersed into the air. Therefore, radon concentrations in the open air environment will be small. However, if the radon gas enters the enclosed space, especially through the floor of the house, its concentration will increase. (Read Sub Branches of Analytical Chemistry)
The average effective dose of this radon gas is about 1.2 mSv (120 mrem) per year. Since the average total dose (either from natural or artificial radiation) is about 2.8 mSv (280 mrem) per year, the contribution of this radon is about 43% of the total dose we receive. Therefore, we must be aware of the radiation dose derived from this radon gas. To reduce radiation from radon gas, the building space must have sufficient ventilation so that the radon gas can be dispersed by air.