Oxiden

Oxiden is the plural form of oxide in Dutch and related languages, used to refer to the chemical class of compounds containing oxygen bound to another element. In English, the standard plural is oxides. When encountered in multilingual texts, oxiden may simply be the language-specific plural form.

An oxide is a chemical compound consisting primarily of oxygen with one or more elements. The simplest oxides have the general form ExOy, representing elements with oxygen. They can be ionic, covalent, or display mixed bonding, and many oxides show nonstoichiometry, meaning the exact ratios of elements can vary from the ideal.

Oxides are broadly categorized as metal oxides and nonmetal oxides. They include derivatives such as peroxides and, in some contexts, superoxides, which have extra oxygen in their structure. Oxides can be basic, acidic, or amphoteric, depending on how they react with acids or bases.

Oxides occur widely in nature as minerals and are produced industrially by oxidation of elements, calcination of metals, or combustion processes. Common examples include aluminum oxide (Al2O3), iron oxide (Fe2O3 or Fe3O4), and silicon dioxide (SiO2), which appears as quartz.

Properties vary across the class. Many metal oxides are ionic solids with high melting points, while nonmetal oxides are often covalent and can be gases or liquids at room temperature. Some oxides serve as transparent ceramics or pigments; others act as semiconductors or catalysts.

Uses and relevance of oxides span materials science, construction, ceramics, glassmaking, catalysis, and electronics. Environmental considerations include oxide gases such as nitrogen oxides and sulfur oxides formed during combustion, which can be pollutants and precursors to acid rain.