Question

question 32
which of the following sizes of syringe should a pharmacy technician use to draw 4.2 ml of potassium chloride?

1 ml
3 ml
10 ml
5 ml

Explanation:

Identify the target volume

The target volume of potassium chloride to be drawn is \(4.2\text{ mL}\).

Evaluate syringe capacity rules

Using the Compounding Packaging Selection concept, a syringe should be chosen such that its total capacity is closest to but greater than or equal to the volume being measured. To maintain accuracy, a syringe should not be filled to more than its maximum capacity, nor should it be used to measure a volume less than \(20\%\) of its total capacity.

Compare the available options

• \(1\text{ mL}\): Too small to hold \(4.2\text{ mL}\).
• \(3\text{ mL}\): Too small to hold \(4.2\text{ mL}\).
• \(5\text{ mL}\): This syringe is larger than \(4.2\text{ mL}\) and can safely and accurately measure the volume. The volume \(4.2\text{ mL}\) is \(84\%\) of its total capacity, which is well within the optimal accuracy range.
• \(10\text{ mL}\): While it can hold \(4.2\text{ mL}\), it is less accurate than a \(5\text{ mL}\) syringe because the graduations on a larger syringe are further apart, making precise measurement of \(4.2\text{ mL}\) more difficult.

Select the optimal syringe size

The \(5\text{ mL}\) syringe is the smallest available syringe that can hold the entire \(4.2\text{ mL}\) volume, offering the highest measurement accuracy.

Answer:

• 1 mL
• 3 mL
• 10 mL
• 5 mL (Correct answer)