When a solution turns red litmus blue, its pH is likely to be: MCQ with Answer and Explanation

When a solution turns red litmus blue, its pH is likely to be:
A. 7
B. 1
C. 4
D. 10
Answer: Option D
Solution (By JKExamLibrary)
Red litmus turning blue indicates that the solution is basic. Basic solutions have a pH greater than 7. Among the options, 10 is the only value greater than 7. pH 1 and 4 are acidic (turn blue litmus red), and 7 is neutral (no change in litmus color).

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