CBSE 2025 · Region 3 · Set 1 · Q1 · 1 mark
Consider the following chemical equation : \[\mathrm{pAl}+\mathrm{q} \mathrm{H}_{2} \mathrm{O} \longrightarrow \mathrm{rAl}_{2} \mathrm{O}_{3}+\mathrm{s} \mathrm{H}_{2} \] To balance this chemical equation, the values of 'p', 'q', 'r' and 's' must be respectively:
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle 2, 3, 1, 3$
Chemical Reactions and EquationsWriting and Balancing Chemical EquationsApplymcqeasy
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CBSE Class 10 Science past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.