Zinc molybdate
Encyclopedia
Zinc molybdate is an inorganic chemical compound
. It is a white pigment
, which can be used as corrosion inhibitor
. While highly soluble
molybdate
s like e.g. sodium molybdate
are toxic in higher doses, zinc molybdate is essentially non-toxic because of its insolubility in water. Molybdates possess a lower toxicity than chromates or lead salts and are therefore seen as an interesting alternative to these salts for corrosion inhibition. It can be synthesized by mixing aqueous solutions of sodium molybdate and zinc chloride
: the insoluble zinc molybdate will crystallize from this mixture.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
. It is a white pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
, which can be used as corrosion inhibitor
Corrosion inhibitor
A corrosion inhibitor is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy. The effectiveness of a corrosion inhibitor depends on fluid composition, quantity of water, and flow regime...
. While highly soluble
Solubility
Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid, or gaseous solvent to form a homogeneous solution of the solute in the solvent. The solubility of a substance fundamentally depends on the used solvent as well as on...
molybdate
Molybdate
In chemistry a molybdate is a compound containing an oxoanion with molybdenum in its highest oxidation state of 6. Molybdenum can form a very large range of such oxoanions which can be discrete structures or polymeric extended structures, although the latter are only found in the solid state.The...
s like e.g. sodium molybdate
Sodium molybdate
Sodium molybdate, Na2MoO4, is useful as a source of molybdenum. It is often found as the dihydrate, Na2MoO4·2H2O.The molybdate anion is tetrahedral. Two sodium cations coordinate with every one anion.-History:...
are toxic in higher doses, zinc molybdate is essentially non-toxic because of its insolubility in water. Molybdates possess a lower toxicity than chromates or lead salts and are therefore seen as an interesting alternative to these salts for corrosion inhibition. It can be synthesized by mixing aqueous solutions of sodium molybdate and zinc chloride
Zinc chloride
Zinc chloride is the name of chemical compound with the formula ZnCl2 and its hydrates. Zinc chlorides, of which nine crystalline forms are known, are colorless or white, and are highly soluble in water. ZnCl2 itself is hygroscopic and even deliquescent. Samples should therefore be protected from...
: the insoluble zinc molybdate will crystallize from this mixture.