Question

A solution turns phenolphthalein indicator pink. The most likely pH of this solution will be ______.

Options

• 6

• 4

• 9

• 7

Answer 1

A solution turns phenolphthalein indicator pink. The most likely pH of this solution will be 9.

Explanation:

Phenolphthalein is a synthetic indicator that remains colourless in acidic and neutral solutions but turns pink in basic environments. This distinct colour change typically occurs when the pH rises above 8.2, confirming that the solution is alkaline. Among the given options, only 9 is a basic pH value, making it the most likely pH of the solution.