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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 thorough-understanding
Consider the unbalanced equation: Al + Cl₂ → AlCl₃. Which of the following correctly balances it? (A) Al + Cl₂ → AlCl₃ (B) 2Al + 3Cl₂ → 2AlCl₃ (C) Al + Cl₃ → AlCl₃ (D) 2Al + Cl₂ → 2AlCl
  1. A Al + Cl₂ → AlCl₃
  2. B 2Al + 3Cl₂ → 2AlCl₃
  3. C Al + Cl₃ → AlCl₃
  4. D 2Al + Cl₂ → 2AlCl
Generated by claude-sonnet-4-6 · 2026-06-26 00:53 · grounding rag
Model Answer

(B) 2Al + 3Cl₂ → 2AlCl₃

LHS: 2 Al, 6 Cl atoms. RHS: 2 Al, 6 Cl atoms — both sides are equal, so the equation is balanced.

Explanation

To balance Al + Cl₂ → AlCl₃, apply the hit-and-trial method. AlCl₃ needs 3 Cl atoms, but Cl₂ provides 2 — so use 3 Cl₂ (6 Cl atoms) and 2 AlCl₃ (6 Cl atoms), then balance Al with coefficient 2. Options C and D use incorrect formulae/products, violating the rule that formulae cannot be altered during balancing.

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