Caesium (Cs) Fun Facts
"Father Time, the most reactive hero, whose atomic vibrations define the second itself."
The true essence of Caesium (Cs) on the molecular frontier.
Caesium is a soft, silvery-gold alkali metal.
Caesium is found in the atomic clocks that regulate GPS and the internet.
Caesium provides the basis for hyper-accurate timekeeping needed for interstellar navigation.
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Did You Know?
It is considered the most reactive of all the metals on the periodic table; it reacts explosively with water and can ignite spontaneously in air.
The official definition of a second is based on the vibrations of a caesium-133 atom. Caesium atomic clocks are so accurate they would only lose about one second in 300 million years.
Caesium has a silvery-gold appearance and is one of only five elemental metals that are liquid at or near room temperature.
It was the first element to be discovered using a spectroscope, identified by its two bright blue spectral lines. Its name comes from the Latin 'caesius', meaning 'sky-blue'.
It is so reactive that it is stored in sealed glass ampoules under an inert atmosphere.