Words for colors

In compounds, the important oxidation numbers of Cr are +2, +3, and +6. In all of these states the chromium ions are colored and, in fact, the element got its name from this property (ichroma is the Greek word for color). The +2 state is not frequently encountered but it can be made quite easily as the beautiful blue chromous ion in solution by dripping a solution containing CrM over metallic zinc. Air has to be excluded since O rapidly converts Cr1-5 back into Cr. ... 

The presence of certain absorption bands in visible and ultraviolet spectra can often be traced to the presence of characteristic groups of atoms in the molecules. These groups of atoms are called chromophores, front the Greek words for color bringer. ... 

Chromium, Cr, is a bright, lustrous, corrosion-resistant metal. Its name, which comes from the Greek word for color, was inspired by its colorful compounds. The metal is obtained from the mineral chromite, FeCr204, by reduction with carbon in an electric arc furnace ... 

When a crystal of an alkali halide has the vapor of the alkali metal passed over it, the alkali halide crystal becomes colored. The reason for this is that a type of defect that leads to absorption of light is created in the crystal. Such a defect is known as an F-center because the German word for "color" is Farbe. It has been shown that such a defect results when an electron occupies a site normally occupied by an anion (an anion "hole"). This arises as a result of the reaction... 

The colored patterns that appear gave rise to the name chromatography, which comes from the Greek words for color writing. ... 

Chromium, which gets its name from the Greek word for color (chroma), is obtained from the ore chromite, a mixed metal oxide with the formula FeO Cr203, or FeCr204. Reduction of chromite with carbon gives the alloy fer-rochrome, which is used to make stainless steel, a hard, corrosion-resistant steel that contains up to 30% chromium. 

Chromium comes from the Greek word for color. In these bottles, the different shades represent variotis colors tf chromium compounds. YOAV LEVY/PHOTOTAKE NYC. 

The formation of color centers in the alkali halides, especially silver, has been studied extensively and in great detail, in an attempt to understand the photographic process. At least half a dozen color centers have been identified in these materials, of which the most widely studied is probably the F center, defined as an electron trapped at an anion vacancy. The name comes from the German word for color Farbe. In the case of KBr, the F center (Fig. 16.7) is believed to be an electron trapped at a bromine vacancy. The F center can be modeled by assuming the electron is trapped in a box of side d, which scales with the lattice parameter of the alkali halide. The F center transition is believed to be between the ground and first excited state of this particle in a box. This model, while crude, qualitatively explains the data for some of the alkali halide F center spectra. 

The first detailed description of chromatography is generally credited to Michael Tswett, a Russian biochemist, who separated chlorophyll from a mixture of plant pigments in 1906. Because erf the nature of the pigments in the sample, each band had a distinctive color. Thus the name of the process was coined from the Greek words for color (chromo) and to write" (graphy). 

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