Search results
Results from the WOW.Com Content Network
A chromate ester is a chemical structure that contains a chromium atom (symbol Cr) in a +6 oxidation state that is connected via an oxygen (O) linkage to a carbon (C) atom. The Cr itself is in its chromate form, with several oxygens attached, and the Cr–O–C attachment makes this chemical group structurally similar to other ester functional groups.
Feedbooks was a digital library and cloud publishing service for both public domain and original books founded in June 2007 and based in Paris, France. [1] The main focus of the web site is providing e-books with particularly high-quality typesetting in multiple formats, particularly EPUB, Kindle, and PDF formats.
Cadmium chromate; Caesium chromate; Calcium chromate; Chromate ester; Chromated copper arsenate; Template:Chromates and dichromates; Chrome orange; Chrome yellow; Chromic acid; Chromium(VI) oxide peroxide
Like conventional esters, the formation of this chromate ester is accelerated by the acid. These esters can be isolated when the alcohol is tertiary because these lack the α hydrogen that would be lost to form the carbonyl. For example, using tert-butyl alcohol, one can isolate tert-butyl chromate ((CH 3) 3 CO) 2 CrO 2), which is itself a good ...
Analogues derived from oxygen replaced by other chalcogens belong to the ester category as well (i.e. esters of acidic −SH, −SeH, −TeH, −PoH and −LvH groups). According to some authors, organyl derivatives of acidic hydrogen of other acids are esters as well (e.g. amides), but not according to the IUPAC. [1]
In organic chemistry and biochemistry esters are the functional group (R'-COOR") consisting of an organic radical united with the residue of any oxygen acid, either organic or inorganic. An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R").
The hydrogen chromate ion may be protonated, with the formation of molecular chromic acid, H 2 CrO 4, but the pK a for the equilibrium H 2 CrO 4 ⇌ HCrO − 4 + H + is not well characterized. Reported values vary between about −0.8 and 1.6. [4] The dichromate ion is a somewhat weaker base than the chromate ion: [5]
Potassium dichromate, K 2 Cr 2 O 7, is a common inorganic chemical reagent, most commonly used as an oxidizing agent in various laboratory and industrial applications. As with all hexavalent chromium compounds, it is acutely and chronically harmful to health.