Chlorine, a pale green gas, was first discovered in 1774 by the Swedish chemist Carl Wilhelm Scheele who called it dephlogisticated muriatic acid. In 1810, Sir Humphrey Davy realized it was an element and renamed it Chlorine, from the Greek meaning “light green”. Chlorine is a member of the Halogen series (Group 17) on the Periodic Table.
Chlorine gas is made up of two atoms of the element (Cl2). Chlorine gas is a deadly poison and was one of the first poison gas weapons used in World War I. Chlorine is more often found in Nature as the negative ion, Chloride, which is decidedly not poisonous. Sodium Chloride, common salt, makes up almost 2% of the ocean, some of which can be seen nearby. Industrially, Chlorine is produced by passing an electric current through salt brine, producing both hydrogen and chlorine gases.
Chlorine has many different uses, from pool disinfectants to laundry bleach to kosher salt to plastic PVC pipes (which shouldn’t be used as cache containers, by the way…). It is found in chlorofluorocarbons which are infamous for drifting up from your spray can to deplete the ozone layer.
In the Bay Area, chlorine is found as sodium chloride in the salt evaporation ponds lining the south end of San Francisco Bay. See Element #11 nearby for all the details.
The cache is a black-taped plastic container, and is placed outside the fence of the nearby office park.
FTF pin in the cache for the lucky FTFer. The nearest legal parking is by this cache, and the cache is kid-friendly if you follow the trail.