Question
I have wild strawberries in an established lawn.  What chemical will work best to get rid of them without harming the lawn.

Answer
That depends upon the type of grass that you have; and I am talking about the scientific name right down to the variety. The reason why this is so important is that some turf varieties are harmed by a weedkiller that is safe on another species of grass or even another variety of the same species.
This is decidedly a case of "Know your turf" and "Read the Label".