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List of all known oxides

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Why is there a list at all? If we need a list then the short list of elements that do NOT form an oxide would be more informative.--Axiosaurus (talk) 09:03, 18 April 2008 (UTC)[reply]

I support removing the list and replacing it with a link Category:Oxides, with a statement that all elements except a handful form oxides, usually lots of oxides per element. WE editors like lists but in the case of oxides, such a list implies a finiteness that is naive and misleading, as well as impractically long. WE has lists of ligands, but every known compound except a few (mostly those that do not form oxides) would serve as a ligand.--Smokefoot (talk) 12:22, 21 April 2008 (UTC)[reply]
  • I agree with getting rid of the list. It's of questionable usefulness for its length. Why not just link to Category:Oxides instead? Alternatively, get rid of most of the entries and select only a small handful of the most representative oxides, similar to what I did to Polyatomic ion (which used to contain an unwieldy long list of purportedly all polyatomic ions... riiight).—Tetracube (talk) 17:40, 23 April 2009 (UTC)[reply]

Solubility

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The section of "solubility" is badly written. It does not explain why most of the oxides is not soluble in water, neither does it explain the relation between instability of O2− in water with oxide's solubility. Hope anyone pass-by can improve it.

Salt (talk) 09:51, 19 December 2009 (UTC)[reply]

Oxide table

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H He
Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Fl Uup Lv Uus Uuo
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
Oxides
No known oxides 1 known oxide 2 known oxides 3 or more known oxides

Here's a draft of a possible oxide table as discussed above. 28bytes (talk) 22:13, 25 October 2010 (UTC)[reply]

Great, but the trouble is "known" here merely means existence of wikipedia articles. Example: we've got only one article on technetium oxide, but more are mentioned in technetium, and even if not mentioned, this doesn't guarantee the number. Another problem is many elements form a large number of non-stoichimetric oxides, which are rarely listed on wikipedia. Materialscientist (talk) 22:27, 25 October 2010 (UTC)[reply]
Would dropping the legend and color-coding be better, then? Or perhaps replacing it with a coloring scheme based on something else? 28bytes (talk) 22:42, 25 October 2010 (UTC)[reply]
I agree - the table is well intentioned and actually very nice if one knows the facts and the extraordinary complications associated with these materials. But the table is also extremely naive and very, very misleading, which we cannot expect our readers to sort out.--Smokefoot (talk) 22:43, 25 October 2010 (UTC)[reply]
A first thought is to replace the number of oxides with their classification to basic, acidic and amphoteric, but, as all information, this would need to be properly referenced (not just to wikipedia itself). Materialscientist (talk) 22:48, 25 October 2010 (UTC)[reply]
Here's another crack at it, with minimal coloring: just a simple "click on the element to get information about its oxide(s)" template. 28bytes (talk) 12:05, 26 October 2010 (UTC)[reply]
  • great idea to turn the list into a periodic table (something like Periodic Systems of Small Molecules), as a coincidence I was already working on the hydrides . The single reference on the oxide page also includes a periodic table of the oxides (binary compounds highest oxidation state). The exceptions to expected behavior are mentioned in the text. It is very informative to see how groups of elements cluster with respect to properties. Many university textbook on inorg chemistry handle inorg chem through these kind of tables. Issues to sort out non-stoichiometric compounds (call them ABx) and multiple compounds for each binary compound. Relevant physical properties (melting point , boiling point) could also be listed in the corners of each cell. V8rik (talk) 22:06, 26 October 2010 (UTC)[reply]

I love the idea, but how about instead showing the major binary structure types (whatever is room temp stable)? So, I guess there would be like

-rock salt for alkaline earths -Bixbyite for a lot of the rare earths -rutile for SnO2 (and TiOd?) -gasses for some of them

If you don't like it in the graphic, could still be some good sortable wikitable...

TCO (talk) 05:39, 29 January 2012 (UTC)[reply]

Sheesh this page needs major work

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Am scared to look at how high the hits are. EVen just on chemistry, (listing major trends in structure and the like) this page is lacking. Not to mention a broader disucsion of the topic (major applications, other?) TCO (talk) 05:30, 29 January 2012 (UTC)[reply]

Couldn't help myself. It is 18,000. (Sue Gardiner, this is not the sort of page that will be built by Facebookers dropping in and dumping unreffed sentences ad hoc. It needs at least a grad student level person to care about it and at least put the major structure together. We should think about how to attract those peoples. Seriously. We can still go after the Global South and the Facebookers. Doesn't need to be one or the other...but we should do something to attract more semi-experts here.)TCO (talk) 05:35, 29 January 2012 (UTC)[reply]

This page is way to complex. Half this crap is irrelevant. — Preceding unsigned comment added by 69.23.93.49 (talk) 03:44, 2 February 2012 (UTC)[reply]

Expound. What should be pruned, what should be added, and why?TCO (talk) 03:57, 2 February 2012 (UTC)[reply]
  • The article really is in pretty good shape. What do you mean with "crap"? In my view a crap contribution is something like "monkeys have three tails". What sort of crap statements do you see in the article? V8rik (talk) 20:01, 2 February 2012 (UTC)[reply]
For one thing, the writing and comments are abysmal—-in terms of spelling, grammar and style. 108.27.232.106 (talk) 07:25, 6 July 2024 (UTC)[reply]

Well in my view 'crap' is anything with no reference. The problem is without a ref someone can just talk smart and seem right. Like the beginning... at first it stated that 'contains at least one oxygen atom' without the additional fact that it can only contain one other element. Although chemistry students don't need the additional information. To others looking at the page with no prior knowledge they start to think that an Oxide can have more then just one other element in it formula. It sounds confusing but here... before I changed the page to a more correct definition people would think that an Oxide can have more then two elements in its formula... like SiOH (just to throw out something random)or they may think that all that is needed is a O atom for it to be an Oxide. Both of these are wrong. And then I added a more correct definition that says... "a chemical compound that contains at least one oxygen atom and one other element". So essentially what I'm saying is you have a lot of pretty words on this page, but until someone ref's them with respectable sources it kinda is crap. — Preceding unsigned comment added by 69.23.93.49 (talk) 05:25, 4 February 2012 (UTC)[reply]

we differ then on the definition of crap. In the meanwhile the current definition in the lead is referenced, see here, so no real problem exists V8rik (talk) 21:31, 11 February 2012 (UTC)[reply]
Presence of two or more elements, one of which is O, is required for an oxide, but does not guarantee it will be called an oxide. Materialscientist (talk) 05:45, 4 February 2012 (UTC)[reply]
Agreed, I think the expression "binary compound" should be added in the first sentence.--Spmoura (talk) 18:43, 5 November 2012 (UTC)[reply]

Hey, I am neither a chemist nor a wikipedia contributor, but I have been working in materials science for 10+ years now and I found the sentence "most metal oxides are polymeric" VERY misleading; isn't there a better word than "polymeric"? — Preceding unsigned comment added by 193.5.152.107 (talk) 08:13, 8 October 2013 (UTC)[reply]

I think that this article need more quotes, it is very poor in references. — Preceding unsigned comment added by Liuzp1 (talkcontribs) 18:13, 7 November 2017 (UTC)[reply]

this could be moved out of the introduction paragraph

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"Most of the Earth's crust consists of solid oxides, the result of elements being oxidized by the oxygen in air or in water. Hydrocarbon combustion affords the two principal carbon oxides: carbon monoxide and carbon dioxide. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion."

I think it's a bit offtopic, but don't delete it, just move it down. 181.50.178.92 (talk) 22:24, 18 June 2013 (UTC)[reply]

Creating complex oxide article

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I work in a lab that studies complex oxides. My labmates recently noticed that no article on complex oxides exists. I am thinking of making a new, short article on complex oxides. Any objections? I could also just put it in as a section on this page. I prefer giving it its own article, but I may be biased from working on them for five years.Tedsanders (talk) 20:01, 17 June 2015 (UTC)[reply]

An intermediate step is to write a few sentence overview for this article, anchored with a reference to a textbook or monograph on complex oxides. The real hurdles to the article are our abiltiy to (a) create an article that does not cite you or your colleagues and (b) base the article on WP:SECONDARY sources - textbooks and reviews, not journal articles! You'd be surprised how many people say they want to write an article but what they really want is to write something about their own (narrow) work. Typically the lede paragraph define the field of complex oxides. Final advice: Wikipedia has no aspiration to report recent breakthroughs (which rarely are breakthroughs) or hot results. We want settled knowledge. That's my 2 cents. --Smokefoot (talk) 23:42, 17 June 2015 (UTC)[reply]

Which oxides are salts?

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Oxides are often not thought of salts. Darsie42 (talk) 15:58, 27 February 2020 (UTC)[reply]

Uncited material in need of citations

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I am moving the following uncited material here until it can be properly supported with inline citations of reliable, secondary sources, per WP:V, WP:NOR, WP:CS, WP:NOR, WP:IRS, WP:PSTS, et al. This diff shows where it was in the article. Nightscream (talk) 17:42, 29 August 2022 (UTC)[reply]

Extended content

Formation

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Two common routes to oxides are hydrolysis and oxidation by oxygen. The combination of water and oxygen is even more corrosive. Virtually all elements burn in an atmosphere of oxygen or an oxygen-rich environment. In the presence of water and oxygen (or simply air), some elements— sodium—react rapidly, to give the hydroxides. In part, for this reason, alkali and alkaline earth metals are not found in nature in their metallic, i.e., native, form. Cesium is so reactive with oxygen that it is used as a getter in vacuum tubes, and solutions of potassium and sodium, so-called NaK are used to deoxygenate and dehydrate some organic solvents. The surface of most metals consists of oxides and hydroxides in the presence of air. A well-known example is aluminium foil, which is coated with a thin film of aluminium oxide that passivates the metal, slowing further corrosion. The aluminum oxide layer can be built to greater thickness by the process of electrolytic anodizing. Though solid magnesium and aluminum react slowly with oxygen at STP—they, like most metals, burn in air, generating very high temperatures. Finely grained powders of most metals can be dangerously explosive in air. Consequently, they are often used in solid-fuel rockets.[citation needed]

Oxides, such as iron(III) oxide or rust, which consists of hydrated iron(III) oxides Fe2O3·nH2O and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), form when oxygen combines with other elements.

In dry oxygen, iron readily forms iron(II) oxide, but the formation of the hydrated ferric oxides, Fe2O3−x(OH)2x, that mainly comprise rust, typically requires oxygen and water. Free oxygen production by photosynthetic bacteria some 3.5 billion years ago precipitated iron out of solution in the oceans as Fe2O3 in the economically important iron ore hematite.[citation needed]

Reactions

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Reduction

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Apart from carbon, hydrogen or even other metals can also convert metal oxides to the metal:

H2 + CuO → Cu + H2O[citation needed]
Zn + CuO → ZnO + C

Metal oxides can be reduced by organic compounds. This redox process is the basis for many important transformations in chemistry, such as the detoxification of drugs by the P450 enzymes and the production of ethylene oxide, which is converted to antifreeze. In such systems, the metal center transfers an oxide ligand to the organic compound followed by regeneration of the metal oxide, often by oxygen in the air.[citation needed]

Reduction by electrolysis

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Since metals that are reactive form oxides that are stable, some metal oxides must be electrolyzed to be reduced. This includes sodium oxide, potassium oxide, calcium oxide, magnesium oxide, and aluminium oxide. The oxides must be molten before immersing graphite electrodes in them:

2Al2O3 → 4Al + 3O2[citation needed]

Hydrolysis and dissolution

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Oxides reacting only with acids are labeled basic oxides. Those reacting only by bases are called "acidic oxides". Oxides that react with both are called amphoteric. Metals tend to form basic oxides, non-metals tend to form acidic oxides, and amphoteric oxides are formed by elements near the boundary between metals and non-metals (metalloids). This reactivity is the basis of many practical processes, such as the extraction of some metals from their ores in the process called hydrometallurgy.[citation needed]

Oxides of more electropositive elements tend to be basic. They are called basic anhydrides. Exposed to water, they may form basic hydroxides. For example, sodium oxide is basic—when hydrated, it forms sodium hydroxide. Oxides of more electronegative elements tend to be acidic. They are called "acid anhydrides"; adding water, they form oxoacids. For example, dichlorine heptoxide is an acid anhydride; perchloric acid is its fully hydrated form. Some oxides can act as both acid and base. They are amphoteric. An example is aluminium oxide. Some oxides do not show behavior as either acid or base.[citation needed]

The oxide ion has the formula O2−. It is the conjugate base of the hydroxide ion, OH and is encountered in ionic solids such as calcium oxide. O2− is unstable in aqueous solution − its affinity for H+ is so great (pKb ~ −38) that it abstracts a proton from a solvent H2O molecule:[citation needed]

O2− + H2O → 2 OH

The equilibrium constant of aforesaid reactions is pKeq ~ −22[citation needed]

In the 18th century, oxides were named calxes or calces after the calcination process used to produce oxides. Calx was later replaced by oxyd.[citation needed]

Nomenclature and formulas

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Sometimes, metal-oxygen ratios are used to name oxides. Thus, NbO would be called niobium monoxide and TiO2 is titanium dioxide. This naming follows the Greek numerical prefixes. In the older literature and continuing in industry, oxides are named by adding the suffix -a to the element's name. Hence alumina, magnesia and chromia, are, respectively, Al2O3, MgO and Cr2O3.[citation needed]

Special types of oxides are peroxide, O2−
2
, and superoxide, O
2
. In such species, oxygen is assigned higher (less negative) oxidation states than oxide. [citation needed]

Since fluorine is more electronegative than oxygen, oxygen difluoride (OF2) does not represent an oxide of fluorine, but instead represents a fluoride of oxygen.[citation needed]

Examples of oxides

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The following table gives examples of commonly encountered oxides. Only a few representatives are given, as the number of polyatomic ions encountered in practice is very large.[citation needed]

Name Formula Found/Usage
Water (hydrogen oxide) H
2
O
Common solvent, required by carbon-based life
Nitrous oxide N
2
O
Laughing gas, anesthetic (used in a combination with diatomic oxygen (O2) to make nitrous oxide and oxygen anesthesia), produced by nitrogen-fixing bacteria, nitrous, oxidizing agent in rocketry, aerosol propellant, recreational drug, greenhouse gas. Other nitrogen oxides such as NO
2
(nitrogen dioxide), NO (nitrogen oxide), N
2
O
3
(dinitrogen trioxide) and N
2
O
4
(dinitrogen tetroxide) exist, particularly in areas with notable air pollution. They are also strong oxidisers, can add nitric acid to acid rain, and are harmful to health.
Silicon dioxide SiO
2
Sand, quartz
Iron(II,III) oxide Fe
3
O
4
Iron ore, rust, along with iron(III) oxide (Fe
2
O
3
)
Aluminium oxide Al
2
O
3
Aluminium ore, alumina, corundum, ruby (corundum with impurities of chromium).
Zinc oxide ZnO Required for vulcanization of rubber, additive to concrete, sunscreen, skin care lotions, antibacterial and antifungal properties, food additive, white pigment.
Carbon dioxide CO
2
Constituent of the atmosphere of Earth, the most abundant and important greenhouse gas, used by plants in photosynthesis to make sugars, product of biological processes such as respiration and chemical reactions such as combustion and chemical decomposition of carbonates. CO or Carbon monoxide exists as a product of incomplete combustion and is a highly toxic gas.
Calcium oxide CaO Quicklime (used in construction to make mortar and concrete), used in self-heating cans due to exothermic reaction with water to produce calcium hydroxide, possible ingredient in Greek fire and produces limelight when heated over 2,400 °Celsius.