The nurse is administering a Hepatitis B Vaccine labeled as 10 mcg/ml. How many ml should the nurse give for a 5 mcg dose?

To determine the correct volume of the Hepatitis B Vaccine to administer for a 5 mcg dose when the concentration is 10 mcg/ml, we can use the formula:

[ \text{Volume (ml)} = \frac{\text{Desired Dose (mcg)}}{\text{Concentration (mcg/ml)}} ]

In this case, the desired dose is 5 mcg, and the concentration of the vaccine is 10 mcg/ml. Plugging these values into the formula gives us:

[ \text{Volume (ml)} = \frac{5 \text{ mcg}}{10 \text{ mcg/ml}} ]

Calculating this results in:

[ \text{Volume (ml)} = 0.5 \text{ ml} ]

Thus, for a 5 mcg dose, the nurse should administer 0.5 ml of the vaccine, which confirms that this choice matches the correct calculation. This demonstrates a fundamental principle of dosage calculations where the amount of medication needed can be derived directly from its concentration. Understanding this relationship is crucial for accurate dosing in clinical practice.