How many milliliters of potassium chloride (KCl) should be administered if prescribed 20 mEq and the label states 10 mEq/ml?

To determine the correct volume of potassium chloride (KCl) to administer, you can use the prescribed amount and the concentration stated on the label. The prescription is for 20 mEq of KCl, and the concentration given is 10 mEq per milliliter.

To find the volume required, you can divide the total mEq needed by the mEq per milliliter:

[ \text{Volume (mL)} = \frac{\text{Total mEq prescribed}}{\text{Concentration (mEq/mL)}} ]

Substituting the values,

[ \text{Volume (mL)} = \frac{20 \text{ mEq}}{10 \text{ mEq/mL}} = 2 \text{ mL} ]

This calculation shows that 2 mL of KCl is needed to meet the prescription of 20 mEq. Therefore, the administration of 2 mL is the correct choice in this scenario, as it matches the required dosage based on the concentration provided.