Iodine-131, T_1/2 = 8

question 12

Multiple Choice

Iodine-131, t_1/2 = 8.0 days, is used in the diagnosis and treatment of thyroid gland diseases. If a laboratory sample of iodine-131 initially emits 9.95 × 10¹⁸ β particles per day, how long will it take for the activity to drop to 6.22 × 10¹⁷ β particles per day?

• A) 2.0 days
• B) 16 days
• C) 32 days
• D) 128 days
• E) None of the answers is correct.

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Definitions:

Intellectualization

A defense mechanism where reasoning is used to block confrontation with an unconscious conflict and its associated emotional stress.

Post-Traumatic Stress Disorder

A psychiatric disorder that can occur in people who have experienced or witnessed a traumatic event, characterized by flashbacks, anxiety, and persistent disturbing thoughts.

Catastrophic Thinking

An irrational thought leading individuals to believe that something is far worse than it actually is.

Primary Appraisal

The initial evaluation process where an individual assesses the significance of a stressor or threatening event.