Alkynes — Predicted 2026

AI-Predicted Question Angles for UPSC 2026

Based on trend analysis, current affairs, and recurring themes in Alkynes.

Reagent-Product Matching (Stereochemistry)

high

NEET frequently tests the specific outcomes of reactions, especially those with stereochemical implications. Questions asking to identify the reagent that converts an alkyne to a *cis*-alkene or a *trans*-alkene are highly probable. This requires students to recall the specific conditions for Lindlar's catalyst versus Na/liquid ammonia reduction. A slightly more complex variant could involve a multi-step synthesis where one step is such a reduction.

Distinguishing Tests and Acidity of Terminal Alkynes

high

The acidic nature of terminal alkynes and the specific tests (Tollens' reagent, ammoniacal cuprous chloride) used to identify them are fundamental concepts. Questions often involve identifying an unknown hydrocarbon based on its reaction with these reagents, or comparing the acidity of different hydrocarbon classes. This is a classic 'identification' type of question that is a staple in competitive exams.

Kuccherov's Reaction (Hydration) and Tautomerism

medium

The hydration of alkynes, particularly the formation of aldehydes from ethyne and ketones from other terminal alkynes via enol-keto tautomerism, is a unique and important reaction. Questions might ask for the product of hydration of a specific alkyne or require understanding the intermediate formed. The distinction between ethyne's product (aldehyde) and other terminal alkynes' products (ketones) is a common point of confusion and thus a good testable area.