Stannous chromate

Stannous Chromate has been described by Berzelius as a yellow flocculent precipitate resulting on the addition of stannous chloride to an excess of potassium chromate solution. If, however, dilute potassium chromate solution is added in small portions, wdth constant shaking, to stannous chloride, a greenish-white precipitate is produced which is probably chromic stannate. If the tin solution contains free acid the whole remains dissolved, forming a green solution. 

Chromic acid (H2Cr04), tin(2+) salt (2 1) EINECS 253-946-3 Stannous chromate Tin chromate Tin(ll) chromate. Rose-violet pigment used to color paper, porcelain and china. Soluble in H2O. 

According to J. J. Berzelius,23 when stannous chloride is added to an excess of a soln. of potassium chromate, and the liquid agitated, yellow, curdy flocks of stannous chromate are precipitated but if to a soln. of stannous chloride a dil. soln. of potassium chromate be added in small portions at a time, with constant agitation, a greenish precipitate of chromic stannate is formed. If the soln. of the tin-salt contains free acid, no precipitate is formed, and the soln. is green. 

Several types of corrosion inhibitors have been investigated in the last 20 years [53-55] these include calcium and sodium nitrites, sodium benzoate, sodium/potassium chromate, sodium salts of silicates and phosphates, stannous chloride, hydrazine hydrate, sodium fluorophosphate, permanganate, aniline and related compounds, alkalis, azides, ferrocyanide, EDTA and many chelating compounds. However, in terms of field practice and research data, nitrite-based compounds occupy a dominant position. 

Other typical reagents generated for coulometric titrations are hydrogen and hydroxyl ions, redox reagents such as ceric, cuprous, ferrous, chromate, ferric, manganic, stannous, and titanous ions, precipitation reagents such as silver, mercurous, mercuric, and sulfate ions, and complex-formation reagents such as cyanide ion and EDTA [8-10]. 

None, control Copper chromate Ammoniacal copper chromate Ammonium chromate Sodium dichromate Chromium trioxide Stannous chloride Ammoniacal zinc oxide Copper sulfate... 

Derivation Interaction of stannous chloride and sodium chromate. 

Commercial inhibitors are frequently blends of several compounds, thus the mechanistic action can be multiple and difficult to identify. While numerous inhibitors have been suggested, only a small group has been seriously studied. Earlier literature reviews are available (Griffin, 1975 Berke, 1989) these studies have focused mainly on anodic inhibitors, especially calcium nitrite, sodium nitrite, stannous chloride, sodium benzoate and some other sodium and potassium salts (e.g. chromates). 

Silver Nitrate Sodium Thiosulfate Stannous Chloride Tin (II) Chloride Potassium Bisulfite Potassium Hydrogen Sulfite Ammonium Sulfamate Sodium Chlorate Sodium Chromate... 

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