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Because of its considerable stability, chromia is a commonly used pigment. It was originally called viridian. It is used in paints, inks, and glasses. It is the colorant in "chrome green" and "institutional green." Chromium(III) oxide is a precursor to the magnetic pigment chromium dioxide, by the following reaction: [7] Cr 2 O 3 + 3 CrO 3 → ...
CrO3 dissolves in water to make a solution containing H+ and CrO4-- ions, which is a dilute solution of chromic acid. Interestingly, CrO3 shows acid properties without water being present e.g. CaO + CrO3 --> CaCrO4. It is an example of a "Lewis acid" which meets the (broader) definition of an acid suggested by the chemist G.N.Lewis in the 1920s.
A basic oxide, also called a base anhydride (meaning "base without water"), is usually formed in the reaction of oxygen with metals, especially alkali (group 1) and alkaline earth (group 2) metals. Both of these groups form ionic oxides that dissolve in water to form basic solutions of the corresponding metal hydroxide: Alkali metals (Group 1)
This kind of chromic acid may be used as a cleaning mixture for glass. Chromic acid may also refer to the molecular species, H 2 CrO 4 of which the trioxide is the anhydride. Chromic acid features chromium in an oxidation state of +6 (and a valence of VI or 6). It is a strong and corrosive oxidizing agent and a moderate carcinogen.
The use of chromic acid, instead of the normally used sulfuric acid, leads to a slight difference of these oxide layers. [78] The high toxicity of Cr(VI) compounds, used in the established chromium electroplating process, and the strengthening of safety and environmental regulations demand a search for substitutes for chromium, or at least a ...
In organic chemistry and biochemistry, important examples include amino acids and derivatives of citric acid. Although an amphiprotic species must be amphoteric, the converse is not true. For example, a metal oxide such as zinc oxide , ZnO, contains no hydrogen and so cannot donate a proton.
A solid with enough basic strength will absorb an electrically neutral acidic indicator and cause the acidic indicator's color to change to the color of its conjugate base. [15] When performing the gaseous acid adsorption method, nitric oxide is used. [15] The basic sites are then determined by calculating the amount of carbon dioxide that is ...
The Sarett oxidation is an organic reaction that oxidizes primary and secondary alcohols to aldehydes and ketones, respectively, using chromium trioxide and pyridine.Unlike the similar Jones oxidation, the Sarett oxidation will not further oxidize primary alcohols to their carboxylic acid form, neither will it affect carbon-carbon double bonds. [1]