The Isotope Has a Half-Life of 21 Hours

question 50

Multiple Choice

The isotope has a half-life of 21 hours. If a sample initially contains exactly 10000 atoms of , approximately how many of these atoms will remain after one week?

• A) 1250
• B) 78
• C) 39
• D) 0
• E) none of the above

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Definitions:

Addictive

Having the quality of causing users to develop a dependency, often compelling them to repeatedly seek out and use the substance or activity.

Selective Serotonin Reuptake Inhibitors

A class of drugs often prescribed as antidepressants, which work by increasing the amount of serotonin in the brain.

Norepinephrine

A neurotransmitter and hormone that plays a key role in alertness and the fight-or-flight response, also involved in mood regulation.

Serotonin

A neurotransmitter found in the brain that affects mood, appetite, sleep, memory, and learning, often associated with feelings of well-being and happiness.