A vial contains radioactive iodine-131 with an activity of 2.0 mCi/mL. If a thyroid test requires 2.6 m Ci in an "atomic cocktail," how many milliliters are used to prepare the iodine-131 solution?

Question

Express the volume to two significant figures and include the appropriate units.

Answer 1

To find the volume of the iodine-131 solution needed, we need to use the relationship between activity, volume, and radioactivity.

Activity = Volume x Radioactivity

Let's call the volume of the solution V. Now we can plug in the given values:

2.6 m Ci = V x 2.0 mCi/mL

Solving for V:

V = 2.6 m Ci / 2.0 mCi/mL

V = 1.3 mL

Therefore, 1.3 mL of the iodine-131 solution is used to prepare the atomic cocktail.