Question

How many milliliters each of purified water and an isotonic sodium chloride solution should be used to prepare 30 mL of a 1% w/v isotonic solution of fentanyl citrate (E= 0.11)? Separate each volume by a comma.

I need help with this problem. Can you please show me step by step on how to solve this. Thank you.

Answer 1

1% W/V fentanyl citrate means, 1 gram of fentanyl citrate in 100 mL of water. The fentanyl citrate needed for this prescription (30 mL) is, X=1 g* 30 mL/100 mL = 0.3 grams The volume of water needed for preparing isotonic solution is, = (grams of drug) (E value of the drug)/(0.009) = (0.3) (0.11)/(0.009) = 3.66 mL The volume of 0.9% NaCl needed is = 30 mL -3.66 mL = 26.34 mL