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Science (086) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [1] medium initial-understanding
Water is commonly found as a liquid, but in some chemical reactions it is written as H₂O(g) in the equation. What does this notation tell you about the condition under which water participates in such reactions?
Generated by claude-sonnet-4-6 · 2026-06-26 00:53 · grounding rag
Model Answer

H₂O(g) indicates that water is in the gaseous (steam) state, meaning the reaction occurs at a high temperature where water exists as vapour, not liquid.

Explanation

The symbol (g) denotes gaseous state. CBSE expects students to know that physical state symbols — (s), (l), (g), (aq) — make a chemical equation more informative. The examiner awards the mark for correctly identifying (g) = gaseous state / steam / high-temperature condition.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.