{{Element | name=Cesium | symbol=Cs | anumber=55 | amass=132.9 amu | state=solid, but very easily melts | class=[[alkali metal]] | cstructure=Body-Centered Cubic | color=silver with slight gold tinge | date=1860 | discname=[[Bunsen, R.W. and Kirchoff, G.]] | origname=From the Latin ''Caesius'', meaning "sky blue" | uses=removing air traces in vacuum tubes | obtained=lepidolite, pollucite }}
{{Element | name=Cesium | symbol=Cs | anumber=55 | amass=132.9 amu | state=solid, but very easily melts | class=[[alkali metal]] | cstructure=Body-Centered Cubic | color=silver with slight gold tinge | date=1860 | discname=[[Bunsen, R.W. and Kirchoff, G.]] | origname=From the Latin ''Caesius'', meaning "sky blue" | uses=removing air traces in vacuum tubes | obtained=lepidolite, pollucite }}
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'''Cesium''' is an element<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref>in the [[alkali metal]] class of the periodic table. It is so chemically active that it is never found free (in elemental form) in nature, and catches fire on mere exposure to air and almost explodes on contact with water.
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'''Cesium''' is an element<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref> in the [[alkali metal]] class of the periodic table. It is so chemically active that it is never found free (in elemental form) in nature, and catches fire on mere exposure to air and almost explodes on contact with water.
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Cesium is a key component in atomic clocks. [http://physicsworld.com/cws/article/news/25595]
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Cesium is a key component in atomic clocks. <ref>http://physicsworld.com/cws/article/news/25595</ref>
It was discovered by Robert Bunsen and Gustav Kirchoff, using their newly invented spectroscope, and was the first element to be discovered spectroscopically. It (along with [[rubidium]]) was identified by a previously unseen blue spectral line in the analysis of mineral water from a German spa. The name comes from that color.
It was discovered by Robert Bunsen and Gustav Kirchoff, using their newly invented spectroscope, and was the first element to be discovered spectroscopically. It (along with [[rubidium]]) was identified by a previously unseen blue spectral line in the analysis of mineral water from a German spa. The name comes from that color.