Chromium information, including Technical Data, Safety Data and its high purity properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity and thermal properties are included.
Chromium is highly resistant to corrosion. This has led to its use in numerous alloying and steel producing applications. When chromium is added to glass or ceramic glazes, it produces a brilliant green. Chromium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and compounds as submicron and nanopowder. It is also used as a paint pigment for this purpose. Recently, chromites have formed the basis for cathode compositions for oxygen generation and fuel cell applications. Chromium facts, including appearance, CAS #, and molecular formula and safety data, research and properties are
Oxides are available in forms including powders and dense pellets for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Chromium is available in soluble forms including chlorides, nitrates and acetates. These compounds are also manufactured as solutions at specified stoichiometries. Chromium is a Block D, Group 6, Period 4 element. The electronic configuration is [Ar] 3d5 4s1. In its elemental form chromium's CAS number is 7440-47-3. The chromium atom has a radius of 124.9.pm and it's Van der Waals radius is 200.pm.All elemental metals, compounds and solutions may be synthesized in ultra high purity (e.g. 99.999%) for laboratory standards, advanced electronic, metallurgy and optical materials and other high technology advantages. Information is provided for stable (non-radioactive) isotopes. Organo-Metallic Chromium compounds are soluble in organic or non-aqueous solvents. See Analytical Services for information on available certified chemical and physical analysis techniques including MS-ICP, X-Ray Diffraction, PSD and Surface Area (BET) analysis. Chromium was first discovered by Anders Ekeberg in 1802.
Abundance. The following table shows the abundance of chromium and each of its naturally occurring isotopes on Earth along with the atomic mass for each isotope. |
chrome
Chrom
cromo
Crômo
cromo
KromIsotope |
Atomic Mass |
% Abundance on Earth |
Cr-50 |
49.946050 |
4.35 |
Cr-52 |
51.940512 |
83.79 |
Cr-53 |
52.940654 |
9.50 |
Cr-54 |
53.938885 |
2.37 |
Safety Data. The safety data for chromium metal, nanoparticles and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the left margin.
Ionization Energy. The ionization energy for chromium (the least required energy to release a single electron from the atom in it's ground state in the gas phase) is stated in the following table: |
1st Ionization Energy |
652.87 kJ mol-1 |
2nd Ionization Energy |
1590.64 kJ mol-1 |
3rd Ionization Energy |
2987.21 kJ mol-1 |
Conductivity. As to chromium's electrical and thermal conductivity, the electrical conductivity measured as to electrical resistivity @ 20 ºC is 12.9 μΩcm and its electronegativities (or its ability to draw electrons relative to other elements) is 1.66. The thermal conductivity of chromium is 93.7 W m-1 K-1.
Thermal Properties. The melting point and boiling point for chromium are stated below. The following chart sets forth the heat of fusion, heat of vaporization and heat of atomization. |
Heat of Fusion |
15.3 kJ mol-1 |
Heat of Vaporization |
341.8 kJ mol-1 |
Heat of Atomization |
394.51 kJ mol-1 |
| Formula | Atomic Number | Molecular Weight | Electronegativity (Pauling) | Density | Melting Point | Boiling Point |
Vanderwaals radius |
Ionic radius | Energy of first ionization |
| Cr | 24 | 51.996 g.mol -1 | 1.6 | 7.19 g.cm-3 at 20 °C | 1907 °C | 2672 °C | 200.pm | 0.061 nm (+3) ; 0.044 nm (+6) | 652.87 kJ.mol-1 |
| PRODUCT CATALOG | U.S. Operations | Submicron & Nanopowder | Tolling | Ultra High Purity | Sputtering Target | Crystal Growth | Rod, Plate, Powder, etc. | Foil |
