The chemical element chromium belongs to group 6 of the periodic table, which is classified as a group of transition metals. Chromium is also categorized as a refractory metal, which exhibits thermal, corrosion and wear resistance.
In the periodic table, the elements are represented by an atomic symbol, atomic number and atomic mass. The elements are organized horizontally based on increasing atomic numbers, where elements that chemically behave in the same manner are arranged vertically. The rows are referred to as "periods" while the columns are known as "groups" or "families."
Families of elements are usually designated using numbers, letters or a combination of the two. One method of specifying the different groups is by using the numbers one to 18 all the way across the periodic table. The group 6, or group VIB of the standard American designation, includes the elements chromium, molybdenum and tungsten.
Chromium has the atomic symbol Cr and atomic number 24. Compared to molybdenum and tungsten, chromium is the least dense and has the lowest melting and boiling points. Chromium also exhibits two magnetic properties that are not typical of molybdenum and tungsten. Due to its high thermal conductivity, chromium can switch from being antiferromagnetic to being paramagnetic. However, the same tendency is shown by the three elements. An increase in their temperatures causes a drop in their thermal conductivity.