Oxide
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 ( O 2 ) 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
Examples of oxides
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 .
An oxide is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. Oxide itself is the dianion of oxygen, an O atom. Metal oxides thus typically contain an anion of oxygen in the oxidation state of −2. 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 AlO (called a passivation layer) that protects the foil from further corrosion. Individual elements can often form multiple oxides, each containing different amounts of the element and oxygen. In some cases these are distinguished by specifying the number of atoms as in carbon monoxide and carbon dioxide, and in other cases by specifying the element's oxidation number, as in iron(II) oxide and iron(III) oxide. Certain elements can form many different oxides, such as those of nitrogen. other examples are silicon, iron, titanium, and aluminium oxides.