Xenate ion

On page 834, the statement is made Hydrogen xenate ions disproportionate in alkaline solution to yield perxenates. . . . " Can you confirm this assertion based on the Latimer diagrams for xenon ... 

The trioxide is the anhydride ofxenic acid, H2Xe04. In aqueous basic solution, the acid forms the hydrogen xenate ion, HXe04", which further disproportionates to the perxenate ion, XeOe, in which xenon attains its highest oxidation number of +8. 

Xe03 is soluble in water, but does not ionise. However, in alkaline solution above pH 10-5, it forms the xenate ion... 

In aqueous solution XeOs is an extremely strong oxidizing agent (for Xe03 q- 6H+ q-6e A - - Xe q- 3H20 ° = 2.10 V), but may be kinetically slow the oxidation of Mn takes hours to produce Mn02 and days before Mn04 is obtained. Treatment of aqueous XeOs with alkali produces xenate ions ... 

The addition of alkali to Xe03 solutions yields xenate ions [HXeOJ. Although salts of this species can be isolated, solutions containing [HXe04] disproportionate to give the perxenate ion, [Xe06]4", and xenon ... 

Xenate solutions may also be oxidized directly to perxenate with ozone. Solid perxenates are rather insoluble and are unusually stable for xenon-oxygen compounds Most do not decompose until healed above 200 eC. X-ray crystallographic structures have been determined for several perxenates. and they have been found to contain the octahedral XeC ion. which persists in aqueous solution (possibly with proionation to HXeOj"). 

In the presence of OH, the reaction of Xe03 leads to the formation of a hydrogen xenate (HXe04 ) ion ... 

CsHXe04 has been prepared by the reaction of xenon trioxide with aqueous cesium hydroxide in the presence of fluoride ion. The role of the fluoride ion in the preparation of CsHXe04 is not clear, but it seems that it prevents the formation of perxenate. In the absence of the fluoride ion, xenon trioxide and cesium hydroxide form a mixed perxenate and xenate salt. CsHXe04 is stable in air. 

In acid or neutral solution the xenon is present as discrete XeO molecules. In basic solutions a negative ion, HXe04, is formed. In neutral or alkaline solutions the XeO slowly decomposes to xenon and oxygen. In strong base disproportionation takes place to produce per.xenates, salts of. enon(VIII). 

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