Argon: the essentials

Argon is a colourless and odourless gas present to a very small extent in the atmosphere. Argon is very inert (indeed it is referred to as one of the noble gases) and is not known to form true chemical compounds. It makes a good atmosphere for working with air-sensitive materials since it is heavier than air and less reactive than N2. Today, the chemical symbol for argon is Ar but until 1957 its sybol was simply A.

Table: basic information about and classifications of argon.

Argon: historical information

Argon was discovered by Sir William Ramsay, Lord Rayleigh at 1894 in Scotland. Origin of name: from the Greek word "argos" meaning "inactive".

Argon was discovered by Lord Rayleigh and Sir William Ramsay in 1894. It was isolated by examination of the residue obtained by removing nitrogen, oxygen, carbon dioxide, and water from clean air. In fact, air contains less than 1% argon. The atmosphere of Mars contains less than 2% argon. It was recognized by the characteristic lines in the red end of the spectrum.

Argon: physical properties

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Argon: orbital properties

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Isolation: argon is present to a small extent in the atmosphere and is obtained as a byproduct from the liquefaction and separation of air. This would not normally be carried out in the laboratory and argon is available commercially in cylinders at high pressure.

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argon atomic number