Xenon tetroxide

 ( Xenon Compounds ) 

Xenon tetroxide is a chemical compound of xenon and oxygen with molecular formula XeO₄, remarkable for being a relatively stable compound of a noble gas. It is a yellow solid that is stable below −35.9 °Celsius; above that temperature it is very prone to exploding and decomposing into elemental xenon and oxygen (O₂).

All eight of xenon are involved in the bonds with the oxygen, and the oxidation state of the xenon atom is +8. Oxygen is the only Chemical element that can bring xenon up to its highest oxidation state; even fluorine can only give (+6), though attempts to synthesize (+8) are still being made.

Two other short-lived xenon compounds with an oxidation state of +8, and , are accessible by the reaction of xenon tetroxide with xenon hexafluoride. and can be detected with mass spectrometry. The are also compounds where xenon has the +8 oxidation state.

---

Reactions At temperatures above , xenon tetroxide is very prone to explosion, decomposing into xenon and oxygen gases with Δ H = :

Xenon tetroxide dissolves in water to form perxenic acid and in alkalis to form perxenate salts:

Xenon tetroxide can also react with xenon hexafluoride to give xenon oxyfluorides:

---

Synthesis All syntheses start from the , which are accessible from the xenic acid through two methods. One is the disproportionation of xenates to perxenates and xenon:

The other is oxidation of the xenates with ozone in basic solution:

Barium perxenate is reacted with sulfuric acid and the unstable perxenic acid is dehydrated to give xenon tetroxide:

Any excess perxenic acid slowly undergoes a decomposition reaction to xenic acid and oxygen:

Post Comment