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Ch.5 Nuclear Chemistry
Timberlake - Chemistry: An Introduction to General, Organic, and Biological Chemistry 13th Edition
Timberlake13th EditionChemistry: An Introduction to General, Organic, and Biological ChemistryISBN: 9780134421353Not the one you use?Change textbook
Chapter 5, Problem 28a

The dosage of technetium-99m for a lung scan is 20. µCi/kg of body mass. How many millicuries of technetium-99m should be given to a 50.0-kg person (1 mCi = 1000 µCi)

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1
Step 1: Start by identifying the given information. The dosage of technetium-99m is 20. µCi/kg, and the body mass of the person is 50.0 kg. Additionally, note the conversion factor: 1 mCi = 1000 µCi.
Step 2: Calculate the total dosage in microcuries (µCi) by multiplying the dosage per kilogram by the body mass. Use the formula: \( \text{Total dosage (µCi)} = \text{Dosage per kg (µCi/kg)} \times \text{Body mass (kg)} \).
Step 3: Substitute the given values into the formula: \( \text{Total dosage (µCi)} = 20. \text{µCi/kg} \times 50.0 \text{kg} \).
Step 4: Convert the total dosage from microcuries (µCi) to millicuries (mCi) using the conversion factor \( 1 \text{mCi} = 1000 \text{µCi} \). Use the formula: \( \text{Total dosage (mCi)} = \frac{\text{Total dosage (µCi)}}{1000} \).
Step 5: Substitute the calculated total dosage in µCi into the conversion formula to find the dosage in mCi.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Radioactive Dosage Calculation

Radioactive dosage calculation involves determining the appropriate amount of a radioactive substance to administer based on a patient's body mass. In this case, the dosage of technetium-99m is given in microcuries per kilogram of body mass, necessitating a conversion to millicuries for the final dosage. Understanding how to perform these calculations is essential for ensuring patient safety and effective imaging.
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Units of Radioactivity

Units of radioactivity are crucial for understanding how radioactive substances are measured and administered. The microcurie (µCi) and millicurie (mCi) are common units, where 1 mCi equals 1000 µCi. Familiarity with these units allows for accurate conversions and ensures that the correct dosage is given based on the specified units in medical protocols.
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Technetium-99m in Medical Imaging

Technetium-99m is a widely used radioactive isotope in medical imaging, particularly in nuclear medicine for procedures like lung scans. Its properties allow for effective imaging due to its suitable half-life and gamma radiation emission. Understanding its role and dosage is vital for healthcare professionals to optimize diagnostic procedures while minimizing radiation exposure to patients.
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