Stannic chloride, hydrated

Concerning the initiation, we follow Russell [75a] in assuming that it is a second order reaction, the rate of which is independent of monomer concentration. Most probably it involves a complex of monomer with the stannic chloride monohydrate [75a]. In view of the well-known tendency of stannic chloride to form 6-co-ordinate rather than 5-coordinate structures, this idea does not seem too far-fetched. Since the monomer is in great excess over stannic chloride hydrate, the concentration of the complex, Pj-SnCl HjO, will be sensibly equal to that of the monohydrate, i.e. of either the stannic chloride or the water, whichever is the scarcer. Therefore, the rate of initiation Vi5 will be given by... 

Since only a very small fraction of the stannic chloride hydrate appears to be involved in the reaction, there is no method at present of distinguishing between these, and possibly other, alternatives. 

The same form of rate equation and Mayo equation can also be obtained, though with different constants, on the assumption, made by Biddulph and Plesch when first discussing this work [77], that the chain breaking agent is the stannic chloride hydrate itself. Since this reaction too would be subject to deceleration by increasing viscosity, it is also compatible with the curves of Figure 9. 

This acid readily attacks the styrene-staimic chloride (or stannic chloride hydrate) complex and, throu an AdgS process, gives l henylethyl chloride. 

Stannic Chloride, anhydrous Stannic Chloride, hydrated Stannic Phosphide 1827 2440 1433 39 60 41 liquid, toxic, n.o.s. Substituted Nitrophenol Pesticides, solid, toxic, n.o.s. 2779 53... 

Stannic Chloride. Stannic chloride is available commercially as anhydrous stannic chloride, SnCl (tin(IV) chloride) stannic chloride pentahydrate, SnCl 5H20 and in proprietary solutions for special appHcations. Anhydrous stannic chloride, a colorless Aiming Hquid, fumes only in moist air, with the subsequent hydrolysis producing finely divided hydrated tin oxide or basic chloride. It is soluble in water, carbon tetrachloride, benzene, toluene, kerosene, gasoline, methanol, and many other organic solvents. With water, it forms a number of hydrates, of which the most important is the pentahydrate. Although stannic chloride is an almost perfect electrical insulator, traces of water make it a weak conductor. 

Stannic Oxide. Stannic oxide tin(IV) oxide, white crystals, mol wt 150.69, mp > 1600° C, sp gr 6.9, is insoluble in water, methanol, or acids but slowly dissolves in hot, concentrated alkaH solutions. In nature, it occurs as the mineral cassiterite. It is prepared industrially by blowing hot air over molten tin, by atomizing tin with high pressure steam and burning the finely divided metal, or by calcination of the hydrated oxide. Other methods of preparation include treating stannic chloride at high temperature with steam, treatment of granular tin at room temperature with nitric acid, or neutralization of stannic chloride with a base. 

Zinnozyd, n. tin oxide, specif, stannic oxide, tin(IV) oxide, -chlorid, n. stannic chloride, tin(IV) chloride, -hydrat, n. stannic hydroxide, tin(IV) hydroxide, -natron, n. sodium stannate. -salz, n. stannic salt, tin(IV) salt. 

Water has also been shown to be essential for the liquid phase polymerization of isobutylene with stannic chloride as catalyst (Norrish and Russell, 87). The rates of reaction were measured by a dilatometric method using ethyl chloride as common solvent at —78.5°. With a mixture consisting of 1.15% stannic chloride, 20 % isobutylene, and 78.8% ethyl chloride, the rate of polymerization was directly proportional to the amount of added water (up to 0.43% of which was added). A rapid increase in the rate of polymerization occurred as the stannic chloride concentration was increased from 0.1 to 1.25% with higher concentrations the rate increased only gradually. It was concluded that a soluble hydrate is formed and functions as the active catalyst. The minimum concentration of stannic chloride below which no polymerization occurred was somewhat less than half the percentage of added water. When the concentration of the metal chloride was less than about one-fifth that of the added water, a light solid precipitated formation of this insoluble hydrate which had no catalytic activity probably explains the minimum catalyst concentration. The addition of 0.3% each of ethyl alcohol, butyl alcohol, diethyl ether, or acetone in the presence of 0.18% water reduced the rate to less than one-fifth of its normal value. On the other hand, no polymerization occurred on the addition of 0.3 % of these substances in the absence of added water. The water-promoted reaction was halved when 1- and 2-butene were present in concentrations of 2 and 6%, respectively. 

It was suggested that the experimental observations could be explained by assuming that chain propagation is initiated both by positive and negative ions derived from the hydrated stannic chloride ... 

Suggest how hydrated stannic chloride, SnCl4-5H20, might be made, starting with stannous chloride. 

What happens if hydrated stannic chloride is heated (Compare aluminum chloride and bromide, Preparations 25 and 26.)... 

Pyrazolin-5-ones form complexes with both inorganic and organic compounds much more readily than do the 2-pyrazolin-5-ones. The most extensive series of complexes is that formed with a variety of metallic salts. Antipyrine (2,3-dimethyl-l-phenyl-3-pyrazolin-5-one) forms a series of complexes with salts of divalent, trivalent and tetra-valent metals. Two molecules of antipyrine form a complex with one molecule of copper, cadmium, cobalt and zinc salts.266,866,1116 Complexes prepared from metallic nitrates are usually hydrated.1322 There also exists a series of complexes in which three molecules of antipyrine form a complex with one or two molecules of metallic salts. Such complexes form with two molecules of simple ferric salts272 or with one of complex iron cyanides.608 Nitrates of thorium, lanthanum, cerium and samarium also give such complexes.841 This ratio also occurs in some antipyrine complexes with cadmium and zinc thiocyanate.266 A number of salts of rare earths and iron which have complex anions such as thiosulfate, thiocyanate, dithionic acid and complex iron cyanides form complexes in which six molecules of antipyrine are present.405,408 608,841,950 Stannic chloride forms salts containing three or four molecules of antipyrine and hydrochloric acid.46... 

Aluminum bromide, incidentally, shows an interesting type of hydrolysis. With a very little water, such as it absorbs on exposure to moist air, it forms an oxybromide that is insoluble in water, and hydrogen bromide is lost. But if enough water is added at the start, it reacts with considerable evolution of heat to give a clear solution that reacts acid to litmus and probably contains colloidal aluminum hydroxide most of the aluminum, however, is in the form of the very stable hydrated ion Al(OH2)6. The hydrolysis is repressed by the very strong hydration of the cation. A similar hydration occurs when stannic chloride dissolves in water (Experiment 19). 

Stannic oxide, hydrated. See Stannic oxide Stannochlor. See Stannous chloride dihydrate Stannous chloride. See Stannous chloride anhydrous... 

Demachy discovered the crystalline hydrate of stannic chloride and observed... 

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