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Science (086) — CBSE Class 10 board question

Q1. [1] § 1.1.1 Writing a Chemical Equation § 1.1.2 Balanced Chemical Equations
MnO₂ + x HCl → MnCl₂ + y H₂O + z Cl₂ In order to balance the above chemical equation, the values of x, y and z respectively are :
  1. (a) 6, 2, 2
  2. (b) 4, 1, 2
  3. (c) 4, 2, 1
  4. (d) 2, 2, 1
Previously asked in CBSE board exam
2023 31/1/1 Q3
Generated by claude-sonnet-4-6 · 2026-06-14 10:27 · grounding rag
Model Answer

(c) 4, 2, 1

Balancing: MnO₂ + 4HCl → MnCl₂ + 2H₂O + Cl₂. Mn=1, O=2, H=4, Cl=4 on both sides. So x=4, y=2, z=1.

Explanation

Balance each element: 4 HCl provides 4 Cl atoms — 2 go to MnCl₂ and 2 form 1 Cl₂; 4 H atoms form 2 H₂O; 2 O atoms (from MnO₂) form 2 H₂O. All atoms balance. Examiners expect the correct option with brief verification.

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