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(near r.t.) 6.0 g/cm 3: 24 Cr chromium; use: ... (near r.t.) 7.26 g/cm 3: ... 0.17443 g/cm 3 (from 22.947 cm 3 /mole; ...
Historically, the mole was defined as the amount of substance in 12 grams of the carbon-12 isotope.As a consequence, the mass of one mole of a chemical compound, in grams, is numerically equal (for all practical purposes) to the mass of one molecule or formula unit of the compound, in daltons, and the molar mass of an isotope in grams per mole is approximately equal to the mass number ...
Obsolete terms for molar mass include gram atomic mass for the mass, in grams, of one mole of atoms of an element, and gram molecular mass for the mass, in grams, of one mole of molecules of a compound. The gram-atom is a former term for a mole of atoms, and gram-molecule for a mole of molecules. [7]
Chromium(III) oxide is amphoteric. Although insoluble in water, it reacts with acid to produce salts of hydrated chromium ions such as [Cr(H 2 O) 6] 3+. [11] It is also attacked by concentrated alkali to yield salts of [Cr(OH) 6] 3−. When heated with finely divided carbon or aluminium, it is reduced to chromium metal: Cr 2 O 3 + 2 Al → 2 Cr ...
Chromium supplementation in general is subject to a certain amount of controversy as it is by no means clear that chromium is an essential element in human biology. [25] Nevertheless, chromium is an ingredient in total parenteral nutrition, along with other trace minerals. [26] It is also in nutritional products for preterm infants. [27]
Chromium-51 is a synthetic radioactive isotope of chromium having a half-life of 27.7 days and decaying by electron capture with emission of gamma rays (0.32 MeV); it is used to label red blood cells for measurement of mass or volume, survival time, and sequestration studies, for the diagnosis of gastrointestinal bleeding, and to label platelets to study their survival.
A variety of other chromium(III) sulfates are known, but also contain hydroxide or oxide ligands. Most important commercially is basic chromium sulfate, which is thought to be [Cr 2 (H 2 O) 6 (OH) 4]SO 4 (CAS#39380-78-4). [2] It results from the partial neutralization of the hexahydrates. Other chromium(III) hydroxides have been reported. [3]
Group 6, numbered by IUPAC style, is a group of elements in the periodic table.Its members are chromium (Cr), molybdenum (Mo), tungsten (W), and seaborgium (Sg). These are all transition metals and chromium, molybdenum and tungsten are refractory metals.