Electron Gain Enthalpy and Electronegativity — Prelims Strategy

Prelims Strategy

To ace NEET questions on Electron Gain Enthalpy and Electronegativity, a multi-pronged strategy is essential. Firstly, master the definitions of both terms and clearly distinguish between them. Remember EGE is an energy change for an isolated atom, while EN is a relative pulling power in a bond.

Secondly, understand the factors influencing each property: effective nuclear charge, atomic size, and electronic configuration are paramount. For EN, also consider hybridization and oxidation state.

Thirdly, memorize the general periodic trends: EGE generally becomes more negative across a period and less negative down a group; EN increases across a period and decreases down a group. Fourthly, and critically, pay close attention to exceptions and anomalies.

The EGE of fluorine being less negative than chlorine, and the positive EGE of noble gases or elements with stable half-filled orbitals (like nitrogen), are frequently tested. Practice comparing elements from different periods and groups.

For MCQs, carefully read each option, especially distractors that exploit common misconceptions (e.g., confusing EGE with EN, or forgetting the F vs. Cl EGE anomaly). For conceptual questions, think about the underlying atomic structure and electron interactions.

For numerical problems (though rare), ensure correct sign conventions for EGE. Always relate the properties back to the fundamental principles of electron attraction and repulsion.