Oxides, Hydroxides, Halides — Predicted 2026

AI-Predicted Question Angles for UPSC 2026

Based on trend analysis, current affairs, and recurring themes in Oxides, Hydroxides, Halides.

Comparative Basicity/Acidity of Hydroxides/Oxides

high

This is a perennial favorite in NEET. Questions often ask to arrange a set of hydroxides or oxides in increasing or decreasing order of basicity/acidity. This tests the understanding of periodic trends (across a period and down a group) and the factors influencing bond strength and ion release. Students must be able to apply the concept that basicity increases with metallic character and decreases with non-metallic character. Expect questions involving s-block, p-block, and d-block elements.

Hydrolysis of Covalent Halides and Fajan's Rules

medium

The concept of hydrolysis of covalent halides, particularly the role of vacant d-orbitals (e.g., $SiCl_4$ vs $CCl_4$), is a classic differentiator. Coupled with Fajan's rules, which explain the degree of covalent character in nominally ionic compounds, this forms a strong conceptual testing ground. Questions could ask to identify halides that hydrolyze, predict products, or compare covalent character based on cation size and charge. This requires a nuanced understanding of bonding.

Identification of Oxide Types and Oxidation States of Oxygen

high

Simple classification questions (acidic, basic, amphoteric, neutral) are fundamental and frequently asked. Additionally, distinguishing between normal oxides, peroxides, and superoxides based on the oxidation state of oxygen and their characteristic properties (e.g., paramagnetism of superoxides) is a common trap. Students need to be precise in identifying the correct oxygen species and its associated properties.