Element #18


- It was discovered by Lord Rayleigh and Sir William Ramsay in 1894

- Isolated by looking at residue obtained by taking away nitrogen, oxygen, carbon dioxide, and water from clean air

- Recognized by the characteristic lines at the red end of the spectrum

- It wasn’t until 1957 that the symbol was changed from A to Ar

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What are its uses?

- Aragon isotopes are used as precursors the production of radioisotope

- Used in gas filled light bulbs

- Also used as an inert gas shield

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There is no biological role in humans

Geology ( in the universe )

- The air contains less than 1% of Argon

- Found natural rocks and it constitutes 1.3% of earth’s atmosphere by weight

- Mars contains 2% of Argon

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What are its properties?

- Density of a solid is 1616 kg

- Melting point 83.8 ( -308.7 Fahrenheit or -189.3 Celsius)

- Boiling point 87.3 (-302.4 Fahrenheit or -185.8 Celsius)

- Atomic mass is 39.94

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Interesting Facts !!

- Noble gas (very inert)

- Came from the greek word "argos" meaning very inert

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