Question

Two solutions X and Y have pH values of 3.0 and 9.5 respectively. Which of these will turn litmus solution from blue to red and which will turn phenolphthalein from colourless to pink?

September 22, 2024

Answer

Solution X (pH 3.0) → Turns blue litmus red; Phenolphthalein remains colorless.

Solution Y (pH 9.5) → Does not change blue litmus; Turns phenolphthalein pink.

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