Physical and Chemical Properties — Predicted 2026

AI-Predicted Question Angles for UPSC 2026

Based on trend analysis, current affairs, and recurring themes in Physical and Chemical Properties.

Ranking of boiling points for C6 or C7 alkane isomers

high

NEET frequently tests the understanding of how molecular structure, specifically chain length and branching, influences physical properties like boiling point. Extending this to C6 or C7 isomers (e.g., n-hexane, 2-methylpentane, 2,2-dimethylbutane) would be a logical step, requiring students to apply the principles of surface area and van der Waals forces to slightly more complex structures. This assesses a deeper understanding beyond just pentane isomers.

Predicting major and minor products of monobromination of a branched alkane

medium

While monochlorination is common, monobromination introduces the concept of higher selectivity. Bromine radicals are less reactive and thus more selective than chlorine radicals, leading to a more pronounced preference for tertiary over secondary and primary hydrogens. A question involving a branched alkane with multiple types of hydrogens (e.g., 2,3-dimethylbutane) would test this nuanced understanding of halogenation selectivity.

Identifying the catalyst and conditions for converting an alkane to an aromatic compound or a branched isomer.

medium

Questions on specific reagents and conditions for less common but industrially important reactions like isomerisation ($AlCl_3/HCl$) and aromatization ($Cr_2O_3/Al_2O_3$, heat) are common in NEET. A question might present a reaction scheme and ask for the missing catalyst or conditions, or vice-versa, testing recall of these specific details and their purpose.