If you have two solutions, one of pH 7 and one of pH 9, but they are not labeled, which indicator would be used to identify the two, methyl orange or phenolphthalein?
The mid-point of the phenolphthalein indicator is about 9 (from 8.3 to 10) and the range for M.O. is 3.1 to 4.4. Can you take it from here?