You oxides are binary compounds (consisting of two chemical elements) where oxygen atoms are bonded to other elements.
One ionic oxide is formed by the union of oxygen with a metal, already in a molecular oxide, oxygen joins a non-metal.
Some examples of oxides are: rust (iron oxide III), hydrogen peroxide (hydrogen peroxide), lime (calcium oxide) and carbon dioxide (carbon dioxide).
From this, depending on the behavior of certain oxides, they are classified into:
| acid oxides | (ametal + oxygen) |
|---|---|
| Basic Oxides | (metal + oxygen) |
| Neutral Oxides | (ametal + oxygen) |
| Amphoteric Oxides | (anhydrides or basic oxides) |
| mixed oxides | (oxide + oxide) |
| Peroxides | (oxygen + oxygen) |
Classification of Oxides
Acid Oxides (Anhydrides)
Formed by non-metals, acid oxides have a covalent character, and in the presence of water these compounds produce acids and, on the other hand, in the presence of bases they form salt and water.
Examples:
- CO2 (carbon dioxide or carbon dioxide)
- ONLY2 (sulfur dioxide)
Basic Oxides
Formed by metals, basic oxides have an ionic character and when they react with acids they form salt and water.
Examples:
- At2O (sodium oxide)
- CaO (calcium oxide)
Neutral Oxides
Formed by non-metals, neutral oxides, also called “inert oxides”, have a covalent character and receive this name because they do not react in the presence of water, acids or bases.
Examples:
- N2O (nitrous oxide)
- CO (carbon monoxide)
Amphoteric Oxides
In this case, the oxides have a peculiarity, sometimes they behave as anhydrides (acid oxides), sometimes as basic oxides.
In other words, these compounds in the presence of an acid behave as basic oxides and, on the other hand, in the presence of a base, react as acid oxides.
Examples:
- Al2O3 (aluminum oxide)
- ZnO (zinc oxide)
mixed oxides
In this case, the mixed oxides, double or saline, are derived from the combination of two oxides.
Examples:
- Faith3O4 (triferon tetraoxide or magnet stone)
- Pb3O4 (trilead tetraoxide)
Peroxides
They are mostly formed by hydrogen, alkali metals and alkaline earth metals.
Peroxides are substances composed of two oxygen atoms that bond together and, therefore, have the group (O) in their formula.2)2-.
Examples:
- H2O2 (hydrogen peroxide or hydrogen peroxide)
- At2O2 (sodium peroxide)
Read too: Inorganic Functions
Examples of Oxides
| CO | carbon monoxide |
|---|---|
| CO2 | carbon dioxide |
| H2O | Water or hydrogen oxide |
| Cl2O7 | dichlorine heptoxide |
| At2O | sodium oxide |
| read2O | lithium oxide |
| Dog | calcium oxide |
| Good | barium oxide |
| FeO | iron oxide II or ferrous oxide |
| Faith2O3 | iron oxide III or ferric oxide |
| ZnO | zinc oxide |
| Al2O3 | aluminum oxide |
| MnO2 | manganese dioxide |
| Uncle2 | titanium dioxide |
| SnO2 | tin dioxide |
| AT THE2 | nitrogen dioxide |
| Nb2O5 | niobium oxide V |
Oxide characteristics
- They are binary substances;
- Have general formula C2Oy, where y is the charge of the cation (Cy+);
- In oxides, oxygen is the most electronegative element;
- They are formed by the binding of oxygen with other elements, except fluorine.
Read too: Chemical Functions
Main oxides and their applications
Check out below where some oxides are used:
Oxides Nomenclature
In general, the nomenclature of an oxide follows the following order:
Oxide + name of element combined with oxygen
| Name according to type of oxide | |
|---|---|
| ionic oxides |
Examples of fixed-charge oxides: CaO - calcium oxide Al2O3 - aluminum oxide |
|
Examples of oxides with variable charge: FeO - Iron Oxide II Faith2O3 - Iron oxide III | |
| molecular oxides |
Examples: CO - carbon monoxide N2O5 - Dinitrogen pentoxide |
Curiosities
- Acid rain is a phenomenon caused by air pollution. Thus, some oxides present in the atmosphere are responsible for increasing the acidity of rain, namely: sulfur oxides (SO2 and SO3) and nitrogen oxides (N2O, NO and NO2).
- The binary compounds OF2 it's the2F2 are not considered oxides, as fluorine is a more electronegative element than oxygen.
- Although noble gases are little reactive, under special conditions it is possible to create oxides of this family, such as xenon (XeO3 and XeO4).
Test your knowledge of oxides with entrance exam questions and expert commented feedback: Exercises on Inorganic Functions.
