Chlorine, element number 17, was first isolated by German-Swedish chemist Carl Wilhelm Scheele in 1774, and he is generally credited with its discovery. Scheele, however, did not recognize chlorine as an element, mistaking it for a compound, an oxide from the hydrochloric acid he used as a source. British chemist Humphry Davy repeated Scheele’s experiment in 1810 and determined that it was indeed an element. Davy named it chlorine because of the yellow-greenish color of the gas, from the Greek χλωρός (chloros, green) + –ινη (–ine). Davy wrote in the Philosophical Transactions of the Royal Society in that year:
It has been judged most proper [...] to call it Chlorine, or Chloric gas.1
The chemical symbol for chlorine is Cl, taken from two of the first letters of its name.
Copyright 1997-2015, by David Wilton