I need to know how I find out what happens when solutions are mixed?

Question

One question is "What happens when phenolphthalein solution is mixed with hcl solution". I don't just want the answer to this, but can anyone tell me how I'd go about finding out the answer please?

Answer 1

http://en.wikipedia.org/wiki/Phenolphthalein

Answer 2

Phenolphathlein is an indicator, so you would need to find out and know the ranges of pH that it will form a visible color change with.
For phenolphthlein, it is colorless in solutions with pH less than 9, but in solutions with a pH of more than 9, it appears pink.

So when mixed with HCl (acid), it appears colorless.