Sulfur dioxide titrimetric

Titanium Sulfates. Solutions of titanous sulfate [10343-61-0] ate readily made by reduction of titanium(IV) sulfate ia sulfuric acid solutioa by electrolytic or chemical means, eg, by reduction with ziac, ziac amalgam, or chromium (IT) chloride. The reaction is the basis of the most used titrimetric procedure for the determination of titanium. Titanous sulfate solutions are violet and, unless protected, can slowly oxidize ia coatact with the atmosphere. If all the titanium has been reduced to the trivalent form and the solution is then evaporated, crystals of an acid sulfate 3 Ti2(S0 2 [10343-61-0] ate produced. This purple salt, stable ia air at aormal temperatures, dissolves ia water to give a stable violet solutioa. Whea heated ia air, it decomposes to Ti02, water, sulfuric acid, and sulfur dioxide. 

The Karl Fisher titration is one of the most common and most sensitive methods used in the analytical laboratory. The titrimetric determination of water is based on the quantitative reaction of water with an anhydrous solution of sulfur dioxide and iodine in the presence of a buffer that reacts with hydrogen ions. This titration is a two-stage process ... 

Water Transfer about 50 mL of liquid sulfur dioxide into a Karl Fischer titration jar, determine the weight of sample taken, and determine the water content as directed in the Karl Fischer Titrimetric Method under Water Determination, Appendix IIB. 

The titrimetric determination of water using the Karl Fischer reagent (mixture of iodine, sulfur dioxide, pyridine, and methanol) is discussed in detail by Mitchell and Smith (1980). Although the reaction is complex, the net reaction is the reaction of water with iodine in a 2 1 ratio in the presence of pyridine ... 

The titrimetric determination of water by the Karl Fischer method depends on the reaction that takes place quantitatively between water and a reagent consisting of sulfur dioxide and iodine in anhydrous pyridine and methanol. The reaction is carried out in methanol. 

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