Trisulfuric acid

Trisulfuric acid, 23 765 Tris[(dimethylamino)methyl]phenol, 1 536 Tri-t-butoxyalumino hydrides, 13 624 Triterpenoids, 24 555-557 Trithia[9]crown-3, 24 41 Trititanium pentoxide, 25 14... 

Similarly molecules of trisulfuric acid, tetrasulfuric acid,... 

Hexamethyldisiloxane can react with 1, 2 or 3 mol of SO3 to give the disilyl ester of sulfuric, disulfuric, or trisulfuric acid, respectively. Sulfur dioxide is a weak acceptor for the Sn—O bond and can be displaced from its adducts by the stronger isocyanate. ... 

H03S(0S02) 0S03H (n = 2, 3, 5, 6) have been obtained by the reaction of SO3 with K2SO4, the free acids cannot be isolated. Disulfuric and trisulfuric acids are present in oleum, i.e. when SO3 is dissolved in concentrated H2SO4. The salt [N02]2[S30iq] has also been prepared and structurally characterized. Structure 15.53 shows [83010] as a representative of this group of polyoxoanions. 

As for isopoly acids or their salts of sulfur(VI)—i.e., polysulfuric acids or their salts—disulfuric acid and its salts (structure 3) and the nitro-nium salt of trisulfuric acid (structure 4) (14) are the known crystalline... 

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