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?
Express the volume to two significant figures and include the appropriate units.
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.
To find the volume of the iodine-131 solution required for the thyroid test, we can use the formula:
Volume (mL) = Activity (mCi) / Concentration (mCi/mL)
Given:
Activity = 2.6 mCi
Concentration = 2.0 mCi/mL
Substituting these values into the formula, we have:
Volume (mL) = 2.6 mCi / 2.0 mCi/mL
Volume (mL) = 1.3 mL
Therefore, to prepare the iodine-131 solution, you would need approximately 1.3 mL of the solution.
To solve this problem, we need to use the equation:
Activity = (Activity per mL) x (Volume in mL)
We can rearrange the equation to solve for the volume:
Volume in mL = Activity / Activity per mL
Given that the activity is 2.6 mCi and the activity per mL is 2.0 mCi/mL, we can substitute these values into the equation:
Volume in mL = 2.6 mCi / 2.0 mCi/mL
Now, let's calculate the volume:
Volume in mL = 1.3 mL
Therefore, you would need to use 1.3 mL (rounded to two significant figures) of the radioactive iodine-131 solution for the thyroid test.