Can my daughter of 130 lbs take 500mg of amoxicillin?

There is no reason that her weight would prevent her from taking 500mg of amoxicillin.

However, i get the impression that they were not prescribed for her, as a single dose would not be prescribed by a doctor, as it would be useless. I would advise that she go see a doctor to see if she needs a FULL COURSE of antibiotics, and be careful as she may be allergic to penicillin.