Polüatomilised

Polüatomilised is the term used in chemistry to describe chemical species that consist of more than one atom. It covers both molecules and polyatomic ions, in contrast to monatomilised species that consist of a single atom. In practice, polyatomilised substances include a wide range of compounds, from simple diatomic molecules to complex biomolecules.

Examples of polüatomilised substances include water (H2O), carbon dioxide (CO2), ammonia (NH3), and methane (CH4). Polyatomic ions such as sulfate (SO4^2−), nitrate (NO3−), and ammonium (NH4+) are another important category. It is common to distinguish diatomic molecules like O2 and N2 as a specific subset within the broader idea of polüatomilised entities, though some contexts treat them as a separate diatomic category.

Bonding and structure: in polüatomilised species, atoms are typically held together by covalent bonds within the molecule, and by covalent or ionic interactions within polyatomic ions. The arrangement of atoms—molecular geometry—determines properties such as polarity, reactivity, boiling and melting points, and solubility. Predicting shapes and behavior often relies on models like VSEPR theory and molecular orbital theory.

Applications and significance: understanding polüatomilised species is fundamental across chemistry, biochemistry, environmental science, and materials science. The nature of the bonds and geometry influences reaction mechanisms, spectroscopy, acid-base behavior, and the behavior of substances in different phases and environments.

Etymology and usage: the word derives from poly- meaning many and atom, and is used in Estonian-language scientific literature and education to denote entities composed of multiple atoms.