This species is added to starch to convert it to the paper additive di·aldehyde starch. Like an iso·electronic metalloid analog, this species converts between an octahedral ortho form and a tetrahedral meta form. When using organic solvents in which this species is insoluble, lead tetra·acetate can produce similar transformations. This ion reacts with poly·saccharides and glyco·proteins to produce functional groups that react with Schiff stain. In an ozonolysis-like reaction, this ion both performs cleavage, and regenerates (-5[1])(*) osmium tet·roxide. A cyclic ester of this ion forms when its sodium salt cleaves a glycol into two carbonyl compounds. Tellurates (-5[1])are isoelectronic to this anion. (-5[1])An often-mispronounced acid’s conjugate base is, for 10 points, (-5[1])what highest oxyanion of iodine, (10[1]-5[1])with formula IO4-? (10[1])■END■ (10[4]0[3])