A Sample of Phosphorus-32 Is Found to Have an Activity

question 71

Multiple Choice

A sample of phosphorus-32 is found to have an activity of 885 disintegrations per hour (dph) .After 25 hours the activity has decreased to 841 dph.What is the rate constant for the decay of phosphorus-32?

• A) 0.0038 hr^-1
• B) 0.0020 hr^-1
• C) 0.15 hr^-1
• D) 490 hr^-1
• E) 0.12 hr^-1

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Definitions:

Magnetic Resonance Imaging (MRI)

A non-invasive imaging technology that produces three-dimensional detailed anatomical images using strong magnetic fields and radio waves.

Transcranial Magnetic Stimulation (TMS)

A noninvasive method used to stimulate small regions of the brain using magnetic fields, often used in treating depression.

Spinal Cord

A long, thin, tubular structure made up of nervous tissue that extends from the medulla oblongata in the brain down to the lower back, acting as a major part of the central nervous system.

Brain

The organ located in the head of humans and other vertebrates that is the central hub for nervous system activity.