Potassium in 1809, Ludwig Wilhelm Gilbert proposed the name "Kalium" for Davy's "potassium". In 1814, the Swedish chemist Berzelius advocated the name "kalium" for potassium, with the chemical symbol "K". The English and French speaking countries adopted Davy and Gay-Lussac/Thénard's name Potassium, while the Germanic countries adopted Gilbert/Klaproth's name Kalium. The "Gold Book" of the International Union of Physical and Applied Chemistry has designated the official chemical symbol as K. Potassium is the second least dense metal after lithium. It is a soft solid with a low melting point, and can be easily cut with a knife. Freshly cut potassium is
CB military symbol or have been, used by the United States: Material Testing Program EA (Edgewood Arsenal) numbers:<br> CB military symbol Chemical, biological (CB) — and sometimes radiological — warfare agents were assigned what is termed a military symbol by the U.S. military until the American chemical and biological weapons programs were terminated (in 1990 and 1969, respectively). Military symbols applied to the CB agent fill, and not to the entire weapon. A chemical or biological weapon designation would be, for example, "Aero-14/B", which could be filled with GB, VX, TGB, or with a biological modification kit – OU, NU, UL, etc. A