Answer:
2 vials
Step-by-step explanation:
The concentration (C) of the drug in the solution is:
C= 500 mg/5 mL = 100 mg/mL
Each vial with a volume (V) of 10 mL, contains the following mass of drug:
V= 10 mL ⇒ C x V = 100 mg/mL x 10 mL = 1000 mg
As you need 2.00 g, and 1 gram is equivalent to 1000 mg, the mass needed is 2.00 g x 1000 mg/1 g = 2000 mg
Thus, you have to divide the mass you need into the mass of each vial:
(2000 mg)/(1000 mg/vial) = 2 vials
Therefore, you need 2 vials.