Chromium is a solid located in period 4 and in group 6B on the periodic table of elements. Which would classify it as a transition metal. Its crystal structure is cubic and its melting point is 1857.0 degrees C (2130.15 K, 3374.6 degrees F). Chromium's Boiling point is at 2672.0 degrees C (2945.15 K, 4841.6 degrees F). Its atomic number is 24 and is a gray solid. All its stable isotopes are Cr-50, Cr-52, Cr-53, Cr-54 and its unstable are Cr-49 and Cr-51. Chromium's atomic mass is 51.9961 amu. Chromium has 24 protons and 24 electrons. It also has 28 neutrons. The atomic structure of chromium is as follows: on the first level there are 2 electrons, on the second level there are 8 electrons, on the third level there are 13 electrons, and on the fourth level there is one electron. Of Course all the protons and neutrons are in the nucleus.
             In the 18th century an analysis of red lead (PbCrO4, crocoite) from Siberia showed an unidentified material. Louis-Nicholas Vauquelin later identified the unidentified material as chromium oxide in 1797. He started by powdering the red lead and precipitated the lead out through its reaction with hydrochloric acid. That left the chromium oxide. He then heated the oxide in an oven with charcoal as a reducing agent to get the metal chromium. Chromium was also found in an emerald analyzed by Vauquelin. He discovered that the chromium gave the emerald its green color. The word chromium is from the Greek word "chroma" which means color, named this because of the many different colored compounds made with it. A German chemist named Tassaert found chromium in an ore now called chromite, just a few years after Vauquelin discovered it. This ore, Fe (CrO2) 2, is now an important source of chromium.
             Today the element chromium must be separated from its compounds to get it, because it is not found freely in nature. Chromium is a metal that is used in many processes. It is used to form alloy...