If 75 mg of a medication is to be diluted in 250 mL of saline, what is the concentration in mg/mL?

To determine the concentration of the medication in mg/mL, you need to calculate how many milligrams of the medication are present in each milliliter of the saline solution.

First, you take the total amount of medication, which is 75 mg, and divide it by the total volume of the solution, which is 250 mL. The formula for concentration is:

Concentration (mg/mL) = Total mg of medication / Total volume in mL

Substituting the values:

Concentration = 75 mg / 250 mL

Now, performing the division:

Concentration = 0.3 mg/mL

This means that each milliliter of the saline solution contains 0.3 mg of the medication, making the correct answer reflect this calculation. Concentrations can often be a source of confusion, but this straightforward division leads to a clear understanding of how much active ingredient is present in a given volume of solution.