Electron Affinity (Definition Equation)
Formula: A (g) + e⁻ ightarrow A⁻ (g) Δ H = E(ea), where E(ea) is the electron affinity (usually the first electron affinity is negative, exothermic). Applicabl…
Syllabus path: Chemical Theories and Laws › Atomic Structure and Periodic Law
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CSCA Chemistry Formula Reference
Formula and explanation
Formula: A (g) + e⁻ ightarrow A⁻ (g) Δ H = E(ea), where E(ea) is the electron affinity (usually the first electron affinity is negative, exothermic). Applicable Conditions: The process of a gaseous atom gaining an electron to form a gaseous anion. Brief Explanation: Electron affinity measures the ease with which an atom gains an electron. The first electron affinity for most elements is negative (exothermic), indicating energy release upon electron gain. Its magnitude also shows periodic trends, with nonmetals typically having more negative (more exothermic) electron affinities.
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Atomic Structure and Periodic Law
Atomic Structure and Periodic Law Core Concepts and Learning Objectives This section is the microscopic starting point of chemical theory. We will start from the internal structure of atoms, understand the fundamental reasons for periodic changes in elemental properties, and mast…
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