It is a radioactivecolorless, odorless, tasteless  noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium and uranium slowly decay into lead and various other short-lived radioactive elements; radon itself is the immediate decay product natural gas and cancer radium.
Its most stable isotopeNatural gas and cancerhas a half-life of only 3. However, since thorium and uranium are two of the most common radioactive elements on Earth, and they have three isotopes with very long half-lives, on the order of several billions of years, radon will be present on Earth long into the future in spite of its short natural gas and cancer as it is continually being generated.
The decay of radon produces many other natural gas and cancer nuclides known as radon daughters, natural gas and cancer, ending at stable isotopes of lead. Unlike all the other intermediate elements in the aforementioned decay chains, radon is, under normal conditions, gaseous and easily inhaled.
Radon gas is considered a health hazard, natural gas and cancer. Despite its short lifetime, radon gas from natural sources, such as uranium-containing minerals, can accumulate in buildings, especially, due to its high density, in low areas such as basements and crawl spaces.
Radon can also occur in ground water — for example, in some spring waters and hot springs. Epidemiological studies have shown a clear link between breathing high concentrations of radon and incidence of lung cancer. Radon is a contaminant that affects indoor air quality worldwide, natural gas and cancer.
According to the United States Environmental Protection Agencyradon is the second most frequent cause of lung cancer, after cigarette smoking, causing 21, lung cancer deaths per year in the United States. About 2, of these deaths occur among people who have never smoked. While radon is the second most frequent cause of lung cancer, it is the number one cause among non-smokers, according to EPA estimates.
Unlike the gaseous radon itself, radon daughters are solids and stick to surfaces, such as dust particles in the air. If such contaminated dust is inhaled, these particles can also cause lung cancer. Radon is a colorless, natural gas and cancer, odorless, and tasteless gas and painful sex and clomid is not detectable by human senses alone.
At standard temperature and pressureradon forms a monatomic gas with a density of 9. Radon is appreciably more soluble in organic liquids than in water. Being a noble gas, radon is chemically not very reactive, natural gas and cancer. Because radon is natural gas and cancer gas at standard conditions, unlike its parents, it can readily be extracted from them for research.
Radon is a member of the zero- valence elements that are called noble gases, natural gas and cancer. 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, natural gas and cancer.
Early studies concluded that the stability of radon hydrate should be of the same order as that of the hydrates of chlorine Cl 2 or sulfur dioxide SO 2natural gas and cancer, and significantly higher than the stability of the hydrate of hydrogen sulfide H 2 S.
Because of its cost and radioactivity, experimental chemical research is seldom performed with radon, and as a result there are very few reported compounds of radon, all either fluorides or oxides. Radon natural gas and cancer be oxidized by powerful oxidizing agents such as fluorinethus forming radon difluoride.
Because of the short half-life of radon and the radioactivity of its compounds, it has not been possible to study the compound in any detail. Theoretical studies on this molecule predict that it should have a Rn—F bond distance of 2. Natural gas and cancer this reason, antimony pentafluoride together with chlorine trifluoride and N 2 F 2 Sb 2 F 11 have been considered for radon gas removal in uranium mines due to the formation of radon—fluorine compounds.
Radon oxides are among the few other reported compounds of radon ;  only the trioxide RnO 3 has been confirmed. Extrapolation down the noble gas group would suggest also the possible existence of RnO, RnO 2and RnOF 4as well as the first chemically stable noble gas chlorides RnCl 2 and RnCl 4but none of these have yet been found. Radon has no stable isotopes, natural gas and cancer. Thirty-seven radioactive isotopes have been characterized, natural gas and cancer, with atomic masses ranging from to Three other radon isotopes have a half-life of over an hour: The Rn isotope is a natural decay product of the most stable thorium isotope Thand is commonly referred to as thoron.
It has a half-life of Similarly, Rn is derived from the most stable isotope of actinium Ac —named "actinon"—and is an alpha emitter with a half-life of 3. Its four first products excluding marginal decay schemes are very short-lived, meaning that the corresponding disintegrations are indicative of the initial radon distribution. Its decay goes through the following sequence: If a closed volume natural gas and cancer constantly supplied with radon, the concentration of short-lived isotopes will increase until an equilibrium is reached where the rate of decay of each decay product will equal that of the radon itself.
The equilibrium factor is 1 when both activities are equal, meaning that the decay products natural gas and cancer stayed close to the radon parent long enough for the equilibrium to be reached, within a couple of hours.
A detailed explanation of WL is given in Concentration Units. Because of their electrostatic charge, radon progenies adhere to surfaces or dust particles, whereas gaseous radon does not.
Attachment removes them from the air, usually causing the equilibrium factor in the atmosphere to be less than one. The equilibrium factor is also lowered by air circulation or air filtration devices, and is increased by airborne dust particles, including cigarette smoke. In high concentrations, airborne radon isotopes contribute significantly to human health risk.
The equilibrium factor found in epidemiological studies is 0. Radon was the fifth radioactive element to be discovered, in by Ernest Rutherford and Robert B. Owens after uranium, thorium, radium and polonium.
Owens and Ernest Rutherford, at McGill University in Montrealnoticed variations when trying to measure radiation from thorium oxide. InRutherford and Harriet Brooks demonstrated that the emanations are radioactive, but credited the Curies for the discovery of the element. Several shortened names were soon suggested for the three emanations: The likeness of the spectra of these three gases with those of argon, krypton, and xenon, and their observed chemical inertia led Sir William Ramsay to suggest in that the "emanations" might contain a new element of the noble gas family, natural gas and cancer.
InRamsay and Robert Whytlaw-Gray isolated radon, determined its melting temperature and approximate density. In they determined that it was the heaviest known gas. As late as the s, the element was also referred to simply as emanation. InParacelsus described a wasting disease of miners, the mala metallorumand Georg Agricola recommended ventilation in mines to avoid this mountain sickness Bergsucht. The first major studies with radon and health occurred in the context of uranium mining in the Joachimsthal region natural gas and cancer Bohemia.
The presence of radon in indoor air was documented as early as Beginning in the s research was initiated to address sources of indoor radon, determinants of concentration, health effects, and mitigation approaches. In the United States, the problem of indoor radon received widespread publicity and intensified investigation after a widely publicized incident in During routine monitoring at a Pennsylvania nuclear power plant, a worker was found to be contaminated with radioactivity.
A high concentration of radon in his home was subsequently identified as responsible. All discussions of radon concentrations in the environment refer to Rn. While the average rate of production of Rn from the thorium decay series is about the same as that of Rn, the amount of Rn in the environment is much less than that of Rn because of the short half-life of Rn 55 seconds, versus 3.
One WLM is equivalent to 3. The levels of Pb can be measured. The rate of deposition of this radioisotope is weather-dependent, natural gas and cancer. Radon concentrations found in natural environments are much too low to be detected by chemical means.
Radon is produced by the radioactive decay of radium, which is found in uranium ores, phosphate rock, shales, igneous and metamorphic rocks such as granite, gneiss, and schist, and to a lesser degree, in common rocks such as limestone.
Radon concentration can differ widely from place to place. Radon concentration can be much higher in mining contexts. Radon mostly appears with the decay chain of the radium and uranium series Lamictal and excessive sweatand marginally with the thorium series Rn.
The element emanates naturally from the ground, and some building materials, all over the world, wherever traces of uranium or thorium can be found, and particularly in regions with soils containing granite or shalewhich have a higher concentration of uranium.
Not all granitic regions are prone to high emissions of radon. Being a rare gas, it usually migrates freely through faults and fragmented soils, and may accumulate in caves or water. Owing to its very short half-life four days for Rnradon concentration decreases very quickly when the distance from the production area increases. Radon concentration varies greatly with season and atmospheric conditions.
For instance, it has been shown to accumulate in the air if there is a meteorological inversion and little wind. High concentrations of radon can be found in some spring waters and hot springs. Hence, ground water has a higher concentration of Rn than surface waterbecause radon is continuously produced by radioactive decay of Ra present in rocks, natural gas and cancer. Likewise, the saturated zone of a soil frequently has a higher radon content than the unsaturated zone because of diffusional losses to the atmosphere.
The presence of Rn has been inferred later from data obtained from the Lunar Prospector alpha particle spectrometer.
Radon is found in some petroleum. Because radon has a similar pressure and temperature curve to propaneand oil refineries separate petrochemicals based on their boiling points, the piping carrying freshly separated propane in oil refineries can become radioactive because of decaying radon and its products. Residues from the petroleum and natural gas industry often contain radium and its daughters.
The sulfate scale from an oil well can be radium rich, while the water, oil, natural gas and cancer, and gas from a well often contains radon. Radon decays to form solid radioisotopes that form coatings on the inside of pipework. High concentrations of radon in homes were discovered by chance in after the stringent radiation testing conducted at a nuclear power plant entrance revealed that Stanley Watrasan engineer at the plant, was contaminated by radioactive substances.
Some level of radon will be found in all buildings. Radon mostly enters a building directly from the soil through the lowest level in the building that is in contact with the ground. High levels of radon in the water supply can also increase indoor radon air levels.
Typical entry points of radon into buildings are cracks in solid foundations, construction joints, cracks in walls, gaps in suspended floors, gaps around service pipes, cavities inside walls, and the water supply.
Also, the concentration in one room of a building may be significantly different from the concentration in an adjoining room. Most of the high radon concentrations have been reported from places near fault zones; hence the existence of a relation between the exhalation rate from faults and indoor radon concentrations is obvious. The distribution of radon concentrations will generally differ from room to room, and the readings are averaged according to regulatory protocols. Indoor radon concentration is usually assumed to follow a lognormal distribution on a given territory.
Some of the highest radon hazard in the United States is found in Iowa and in the Appalachian Mountain areas in southeastern Pennsylvania.