A vial contains radioactive iodine-131 with an activity of 2.0 mCi/mL. If a thyroid test requires 2.2 mCi 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 to prepare the "atomic cocktail," we can use the formula:

Volume (mL) = Activity (mCi) / Concentration (mCi/mL)

In this case, the activity of the iodine-131 is 2.0 mCi/mL and the required activity for the thyroid test is 2.2 mCi. Plugging these values into the formula:

Volume (mL) = 2.2 mCi / 2.0 mCi/mL = 1.1 mL

Therefore, 1.1 mL of the iodine-131 solution is needed to prepare the "atomic cocktail."