Krypton is a colorless, odorless noble gas (atomic number 36) that exists as a trace element in Earth’s atmosphere. Characterized by very low chemical reactivity, it is one of the six naturally occurring noble gases. The story of how this elusive substance was named directly reflects the difficult circumstances surrounding its discovery in the late 19th century.
Isolating the “Hidden” Element
Krypton was discovered in 1898 by Scottish chemist Sir William Ramsay and his assistant Morris Travers. Their isolation of the element marked a significant moment in understanding atmospheric composition. This work followed Ramsay’s earlier identification of Argon, which motivated them to search for other chemically inert gases.
The researchers used fractional distillation of liquid air to separate the atmosphere’s components. This involved cooling air until it liquefied, then carefully warming it to allow each gas to boil off at its specific temperature. After abundant gases like nitrogen, oxygen, and argon evaporated, a tiny, non-volatile residue remained.
This residue was the source of Krypton, present at a concentration of approximately one part per million by volume in the atmosphere. The small quantity and demanding separation process meant Krypton was effectively concealed within the vast volumes of air processed. The difficulty of the isolation procedure inspired the element’s unique designation.
The Greek Origin of the Name
The name “Krypton” is rooted in the classical language of ancient Greece. The term is derived directly from the Greek adjective kryptos. This linguistic root is shared with English words like “cryptography” and “crypt.”
In Greek, kryptos means “the hidden one,” “concealed,” or “secret.” This definition refers to something not immediately visible or kept from view. The etymological choice deliberately linked the element’s nature to its linguistic origin.
Why the Name Was Chosen
The choice of the name “Krypton” was a direct commentary by Ramsay and Travers on their challenging laboratory experience. Because the element was found only in the minuscule, final fraction of the liquid air residue, it had remained hidden from chemists for centuries, unlike major atmospheric components such as oxygen and nitrogen.
The name was a tribute to the element’s elusive nature and the exhaustive labor required to detect its presence. Krypton’s existence was obscured by the far greater quantities of other gases, demanding precise and complex techniques for separation.