Question

Rx: 325 mL of 30% NaCl Soln. Your Pharmacy stocks 22% and 40% NaCl Soln. How may mL of 22% NaCl Soln would you need to formulate the prescription? (Round to the nearest mL with no units!)

Answer 1

To formulate the prescription, you would need approximately 180 mL of the 22% NaCl solution.

Step-by-step explanation:

To calculate the amount of 22% NaCl solution needed to formulate the prescription, we can use the equation:

(0.22)(V1) + (0.40)(325 mL - V1) = (0.30)(325 mL)

Where V1 represents the volume of 22% NaCl solution.

Simplifying the equation, we get:

0.22V1 + 130 - 0.40V1 = 97.5

Combining like terms, we have:

-0.18V1 = -32.5

Dividing both sides by -0.18 gives us:

V1 ≈ 180 mL

Therefore, approximately 180 mL of the 22% NaCl solution would be needed to formulate the prescription.