General Characteristics of Compounds — Predicted 2026

AI-Predicted Question Angles for UPSC 2026

Based on trend analysis, current affairs, and recurring themes in General Characteristics of Compounds.

Comparative Thermal Stability of Group 1 vs. Group 2 Nitrates

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NEET often tests comparative properties. While individual group trends are common, a question comparing the decomposition products and relative thermal stabilities of, say, $\text{LiNO}_3$ (decomposes to oxide) vs. $\text{NaNO}_3$ (decomposes to nitrite) and then comparing them to a Group 2 nitrate like $\text{Mg(NO}_3)_2$ (decomposes to oxide, $\text{NO}_2$, $\text{O}_2$) could be a slightly more complex, yet fair, question. This tests both the anomalous behavior of lithium and the general decomposition patterns.

Application of Fajan's Rules to explain physical properties

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Beyond just stating that $\text{BeCl}_2$ is covalent, a question might ask to explain why $\text{BeCl}_2$ has a lower melting point than $\text{MgCl}_2$, or why it is soluble in organic solvents, or why it doesn't conduct electricity in the molten state. This requires a deeper application of Fajan's rules and understanding the consequences of covalent character on physical properties, moving beyond simple recall.

Impact of Hydration on Ionic Size and Mobility

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While hydration enthalpy is used to explain solubility, a question might focus on the effective hydrated ionic radius. For example, asking to arrange alkali metal ions in aqueous solution in increasing order of their ionic mobility. The smallest bare ion ($\text{Li}^+$) gets most hydrated, becoming the largest in aqueous solution, and thus has the lowest mobility. This is a classic concept that links hydration to physical properties in solution and is a common trap.