ATI TEAS (Test of Essential Academic Skills) Version 7MathematicsMedium
A patient's medication is supplied in a vial containing 2.5 grams of powder. The instructions state to reconstitute the powder with 5 mL of sterile water to achieve a concentration of 500 mg/mL. How much powder was actually needed for this concentration?
- A5000 mg
- B1250 mg
- C250 mg
- D2500 mg
Show answer & explanationAnswer & explanation
Correct answer: D. 2500 mg
To find the total amount of powder needed, multiply the desired concentration (500 mg/mL) by the volume of sterile water used for reconstitution (5 mL). This gives 2500 mg.
Why the other options are wrong
- A. This would be the amount if 10 mL of water were used.
- B. This is an incorrect calculation, possibly dividing 2.5g by 2 or 5.
- C. This is 500 mg / 2 mL, not the total amount.
Reconstitution Calculation (Powder)
Determining the amount of powdered medication required to achieve a specific concentration when reconstituted with a given volume of diluent.
- Concentration is expressed as mass per volume (e.g., mg/mL).
- Involves multiplying the target concentration by the diluent volume.
- Ensures the final solution has the desired strength.
Memory trick: Concentration times Volume, that's the powder's true sum!