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.
The main hazard is from inhalation of the element and its decay products which
are collected on dust in the air. Recently, radon buildup in homes from the
surrounding
soil and rocks has become a safety issue and some areas around the world test
homes for radon gas. It is the heaviest known gas. Radon is present in some
spring waters.
•Name: Radon
•Symbol: Rn
•Atomic number: 86
•Atomic weight: [ 222 ]
•Standard state: gas at 298 K (the heaviest known mononuclear gas at 298 K)
•CAS Registry ID: 10043-92-2
•Group in periodic table: 18
•Group name: Noble gas
•Period in periodic table: 6
•Block in periodic table: p-block
•Color: colorless
•Classification: Non-metallic
Historical information
Radon was discovered by Friedrich Ernst Dorn at 1900 in Germany. Origin of name is "the element radium" -radon was called niton at first, from the Latin word "nitens" meaning "shining." It is essentially inert (pretty much non-reactive...unless you REALLY work for it). It has been called radon since 1923, before which it was called niton.
Physical properties
•Melting point: 202 [or -71 °C (-96 °F)] K
•Boiling point: 211.3 [or -61.7 °C (-79.1 °F)] K
•Density of solid: 4400 kg m-3
Orbital properties
•Ground state electron configuration: [Xe].4f14.5d10.6s2.6p6
•Shell structure: 2.8.18.32.18.8
•Term symbol: 1S0
Isolation
Radon is present to a very small trace extent in the atmosphere and in principle could be obtained as a byproduct from the liquefaction and separation of air. However as only small quantities are ever needed in practice, and because of its short half life (the longest life isotope has a half life of less than 4 days), such quantities as are required are isolated through collection from the radioactive decay of an isotope of radium (226Ra, half life 1599 years).
226Ra → 222Rn + 4He
•Name: Radon
•Symbol: Rn
•Atomic number: 86
•Atomic weight: [ 222 ]
•Standard state: gas at 298 K (the heaviest known mononuclear gas at 298 K)
•CAS Registry ID: 10043-92-2
•Group in periodic table: 18
•Group name: Noble gas
•Period in periodic table: 6
•Block in periodic table: p-block
•Color: colorless
•Classification: Non-metallic
Historical information
Radon was discovered by Friedrich Ernst Dorn at 1900 in Germany. Origin of name is "the element radium" -radon was called niton at first, from the Latin word "nitens" meaning "shining." It is essentially inert (pretty much non-reactive...unless you REALLY work for it). It has been called radon since 1923, before which it was called niton.
Physical properties
•Melting point: 202 [or -71 °C (-96 °F)] K
•Boiling point: 211.3 [or -61.7 °C (-79.1 °F)] K
•Density of solid: 4400 kg m-3
Orbital properties
•Ground state electron configuration: [Xe].4f14.5d10.6s2.6p6
•Shell structure: 2.8.18.32.18.8
•Term symbol: 1S0
Isolation
Radon is present to a very small trace extent in the atmosphere and in principle could be obtained as a byproduct from the liquefaction and separation of air. However as only small quantities are ever needed in practice, and because of its short half life (the longest life isotope has a half life of less than 4 days), such quantities as are required are isolated through collection from the radioactive decay of an isotope of radium (226Ra, half life 1599 years).
226Ra → 222Rn + 4He
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