If a patient requires 500 mg of a medication and the available concentration is 250 mg/ml, how many ml should be administered?

To determine the appropriate volume of medication to administer based on the required dose and the available concentration, the following calculation is performed:

1. The patient requires a total of 500 mg of the medication.

2. The available concentration of the medication is 250 mg per milliliter (ml).

To find out how many ml contains the needed 500 mg, you can use the formula:

[ \text{Volume (ml)} = \frac{\text{Required Dose (mg)}}{\text{Concentration (mg/ml)}} ]

Substituting the values into the formula:

[ \text{Volume (ml)} = \frac{500 \text{ mg}}{250 \text{ mg/ml}} = 2 \text{ ml} ]

This calculation shows that in order to deliver the necessary 500 mg of the medication, 2 ml must be administered, which matches the correct answer. Understanding this calculation is critical because it ensures the patient receives the correct dosage based on the medication concentration available, thereby promoting effective and safe treatment.