Five solutions, A, B, C, D and E, when tested with a universal indicator, showed pH as 4, 1, 11, 7 and 9, respectively. Which solution is (a) Neutral? (b) Strongly alkaline? (c) Strongly acidic? (d) Weakly acidic? (e) Weakly alkaline?
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
In increasing order of hydrogen ion concentration,
pH 11(C) < pH 9(E) < pH 7 (D) < pH 4 (A) < pH 1 (B)
PH11 – Strongly alkaline
pH9 – Weakly alkaline
PH7 – Neutral
pH4 – Weakly acidic
pH1 – Strongly acidic
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