Mixed oxide

Mixed oxide

In chemistry, a mixed oxide is a somewhat informal name for an oxide that contains more than one chemical element in its cation, or of a single element cation that has atoms in several states of oxidation.

The term is usually applied to solid ionic compounds that contain the oxide anion O2− and two or more element cations. A typical example is the mineral ilmenite (FeTiO3), a mixed oxide of iron (Fe2+) and titanium (Ti4+) cations. The cations may be the same element in different ionization states: a notable example is magnetite Fe3O4, which contains the cations Fe2+ ("ferrous" iron) and Fe3+ ("ferric" iron) in 1:1 ratio. Other notable examples include the ferrites,[1] strontium titanate SrTiO3 (which, despite its name, contains Ti4+ cations and not the TiO32- anion), yttrium aluminum garnet Y3Al5O12,[2] and many more.

Mixed oxides are intermediate between a metal oxide and a metal salt. Sometimes mixed oxides are the salts of weak metallic acids. Most other times they are just two different oxides that bond together strongly.

However, the term is sometimes also applied to compounds of oxygen and two or more other elements, where some or all of the oxygen atoms are covalently bound into oxoanions.[clarification needed][citation needed]; or to fine mixtures of two or more oxides. An example would be the zincates. Zinc hydroxide can react with concentrated sodium hydroxide to become sodium zincate. This contains zincate ions.

Mixed oxide minerals are plentiful in nature. Synthetic mixed oxides are components of many ceramics with remarkable properties and important advanced technological applications, such as strong magnets, fine optics, lasers, semiconductors, piezoelectrics, superconductors, catalysts, refractories, gas mantles, nuclear fuels, and more. Piezoelectric mixed oxides, in particular, are extensively used in pressure and strain gauges, microphones, ultrasound transducers, micromanipulators, delay lines, etc..

References

  1. ^ Alex Goldman (1990), Modern ferrite technology
  2. ^ K. Byrappa, Masahiro Yoshimura (2001), Handbook of hydrothermal technology. William Andrew. 870 pages.

Wikimedia Foundation. 2010.

Игры ⚽ Нужно сделать НИР?

Look at other dictionaries:

  • mixed oxide — mišrusis oksidas statusas T sritis chemija apibrėžtis To paties elemento skirtingo oksidacijos laipsnio junginių su deguonimi mišinys. atitikmenys: angl. mixed oxide rus. смешанный окисел …   Chemijos terminų aiškinamasis žodynas

  • Mixed oxide fuel — См. Смешанное оксидное топливо Термины атомной энергетики. Концерн Росэнергоатом, 2010 …   Термины атомной энергетики

  • mixed oxide catalyst — mišrusis oksidinis katalizatorius statusas T sritis chemija apibrėžtis Katalizatorius, sudarytas iš kelių skirtingo oksidacijos laipsnio metalų oksidų. atitikmenys: angl. mixed oxide catalyst rus. смешанный окисный катализатор …   Chemijos terminų aiškinamasis žodynas

  • Mixed Oxide of Nitrogen — Der Begriff Mixed Oxides of Nitrogen (meistens abgekürzt zu MON) kommt aus dem Englischen und bedeutet „Gemischte Stickstoffoxide“. Es handelt sich um Lösungen von Stickstoffmonoxid (NO) in Distickstofftetroxid/Stickstoffdioxid (N2O4 / NO2). Sie… …   Deutsch Wikipedia

  • mixed oxide — noun Any mixture of the oxides of more than one metal, but especially the blend of plutonium and uranium oxides that is used (as MOX fuel) in nuclear reactors …   Wiktionary

  • Mixed — is the past tense of mix. It may also refer to: Mixed breed, an animal whose parents are from different breeds or species Mixed anomaly, in theoretical physics, an example of an anomaly Mixed data sampling, an econometric model developed by… …   Wikipedia

  • Mixed oxides of nitrogen — (MON) are solutions of nitric oxide (NO) in dinitrogen tetroxide/nitrogen dioxide (N2O4 and NO2). It may be used as an oxidizing agent in rocket propulsion systems. A broad range of compositions is available, and can be denoted as MONi, where i… …   Wikipedia

  • Mixed metal oxide electrode — Mixed metal oxide (MMO) electrodes are devices with useful properties for chemical electrolysis. The term refers to electrodes in which the surface contains two kinds of metal oxides. One kind, usually RuO2, IrO2, or PtO0.12, conducts electricity …   Wikipedia

  • Mixed metal oxide — (MMO) electrodes are devices with useful properties for chemical electrolysis. The term refers to a mixture of platinum group metals used to form the surface of the electrode, which provides efficient electrolytic action while resisting corrosion …   Wikipedia

  • Mixed ether — Ether E ther ([=e] th[ e]r), n. [L. aether, Gr. a iqh r, fr. a i qein to light up, kindle, burn, blaze; akin to Skr. idh, indh, and prob. to E. idle: cf. F. [ e]ther.] [Written also {[ae]ther}.] 1. (Physics) A medium of great elasticity and… …   The Collaborative International Dictionary of English

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”