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प्रश्न
A solution turns phenolphthalein indicator pink. The most likely pH of this solution will be:
(a) 6
(b) 4
(c) 9
(d) 7
उत्तर
9
Every substance with a pH greater than 7 is considered basic or alkaline. Basic or alkaline solutions turn phenolphthalein indicator pink. Thus, the pH of the solution is most likely 9.
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