Question

Pharmacy has 325mL of a 40% solution. 120mL of sterile water is added to this solution to decrease the concentration. How many grams of active ingredient would be in the diluted solution?(just need to know how to set this up please)

Answer 1

No way to tell the number of grams, since we know nothing about the solute.

But in any case, the mass of solute is not changed by adding some water.