CBSE 2025 · Region 1 · Set 3 · Q5 · 1 mark
Tooth enamel is made up of calcium hydroxyapatite (a crystalline form of calcium phosphate). This chemical starts corroding in the mouth when the pH is :
Official answer
From CBSE’s own marking scheme for this paper.
(B)
$\displaystyle 5$
Acids, Bases and SaltspH Scale and its Importance in Everyday LifeRemembermcqmedium
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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.