Trivial name for example, hydrogen ("water-producing"), oxygen ("acid-producing"), nitrogen ("soda-producing"), bromine ("stink"), and argon ("no reaction") were based on Greek roots, while the names of iodine and chlorine were derived from the Greek words for their characteristic colors. Indium, rubidium, and thallium were similarly named for the colors of particular lines in their emission spectra. Iridium, which forms compounds of many different colors, takes its name from "iris", the Latin for "rainbow". The noble gases have all been named for their origin or properties. Helium comes from the Greek "helios", meaning "sun" because it was first detected as a line in the
Organisation for the Prohibition of Chemical Weapons Organisation for the Prohibition of Chemical Weapons The Organisation for the Prohibition of Chemical Weapons (OPCW) is an intergovernmental organisation and the implementing body for the Chemical Weapons Convention, which entered into force on 29 April 1997. The OPCW, with its 193 member states, has its seat in The Hague, Netherlands, and oversees the global endeavour for the permanent and verifiable elimination of chemical weapons. The organisation promotes and verifies the adherence to the Chemical Weapons Convention, which prohibits the use of chemical weapons and requires their destruction. Verification consists both of evaluation of declarations by member states and onsite