|A a measure of the ability of an atom or molecule to form a negative ion, expressed as the energy released when an electron is attached|
|Main Entry:||electron affinity|
|Part of Speech:||n|
|Definition:||the amount of energy needed to remove an electron from a negatively charged ion; also, the energy released when a single electron is combined with an isolated atom|
in chemistry, the amount of energy liberated when an electron is added to a neutral atom to form a negatively charged ion. The electron affinities of atoms are difficult to measure, hence values are available for only a few chemical elements, chiefly the halogens. These values were obtained from measurements of heats of formation and lattice energies of ionic compounds of the elements. The electron affinity of an element is a measure of that element's tendency to act as an oxidizing agent (an electron acceptor) and is generally related to the nature of the chemical bonds the element forms with other elements
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