Hello!
If phenolphthalein was added to an ammonia-based solution of window cleaner, we would expect the solution to turn pink.
Phenolphthalein is an indicator that is colorless at pHs under 8,2 and has a pink color at pHs over 8,2. An ammonia-based solution of window cleaner is basic, and given that ammonia, although being a weak base, can have pHs over 8,2 the solution will probably turn pink when adding the indicator phenolphthalein.
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