Chemical element of metals. Cu comes from Cuprum, Fe comes from Ferrum, Ag from Argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin "natrium". The same applies to "W" (wolfram) for tungsten, "Fe" (ferrum) for iron, "Hg" (hydrargyrum) for mercury, "Sn" (stannum) for tin, "K" (kalium) for potassium, "Au" (aurum) for gold, "Ag" (argentum) for silver, "Pb" (plumbum) for lead, "Cu" (cuprum) for copper, and
Potassium picrate Potassium picrate Potassium picrate, or potassium 2,4,6-trinitrophenolate, is an organic chemical, a picrate of potassium. It is a reddish yellow or green crystalline material. It is a primary explosive. Anhydrous potassium picrate forms orthorhombic crystals. Potassium picrate was first prepared as impure in mid-17th century by Johann Rudolf Glauber by dissolving wood in nitric acid and neutralizing with potassium carbonate. It is commonly made by neutralizing picric acid by potassium carbonate. It was used since 1869. Its chief applications are in pyrotechnics, in some whistle mixes, as a component of explosives (with potassium nitrate and charcoal), propellants (with potassium chlorate),