Elektroujemno

Elektroujemno is a chemical property describing the tendency of an atom to attract electrons toward itself when forming a chemical bond. It helps explain why bonds are polar, how electron density is distributed in molecules, and why some elements influence acidity and basicity in reactions. In many languages, including several Slavic languages, the term corresponds to electronegativity.

Elektroujemno is quantified using several scales. The Pauling scale assigns dimensionless values based on bond dissociation energies, with fluorine at 3.98, oxygen at 3.44, nitrogen at 3.04, chlorine at 3.16, carbon at 2.55, and hydrogen at 2.20. The Mulliken scale defines electronegativity as the average of an atom’s ionization energy and electron affinity. The Allred–Rochow scale derives a value from the effective nuclear charge divided by covalent radius. Although each scale uses different references, they aim to rank elements by their tendency to attract electrons.

In the periodic table, elektroujemno generally increases across a period and decreases down a group. Nonmetals typically exhibit higher electronegativity than metals, and elements such as fluorine and oxygen are among the most electronegative. Electroujemnost correlates with ionization energy and electron affinity and is a key factor in predicting bond polarity, molecular dipole moments, and reaction mechanisms.

Limitations include dependence on chemical environment and bonding context. Elektroujemno is not an intrinsic constant of a free atom; it varies with oxidation state, coordination, and neighboring atoms. Consequently, numerical values depend on the chosen scale, though relative trends remain informative. See also Ionization energy, Electron affinity, Polar covalent bond, and Periodic trends.