Radioactive Elements Decay Via First-Order Kinetics

question 21

Multiple Choice

Radioactive elements decay via first-order kinetics. Consider a certain type of nucleus that has a rate constant of 1.0  10^-3 h^-1. A sample contains 5.0  10⁹ radioactive nuclides. Calculate the number of nuclides remaining after 39 days have passed.

• A) 64
• B) 7.8  10^-11
• C) 2.0  10⁹
• D) 5.0  10⁹
• E) 2.5  10⁹

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Definitions:

Neutral Stimulus

An environmental event that initially does not elicit any intrinsic response until it is associated with an unconditioned stimulus, leading to a conditioned response.

Pavlov

A Russian physiologist known for his research in classical conditioning, demonstrating how stimuli can trigger a conditioned response.

Salivation

The secretion of saliva, often triggered by the sight, smell, or taste of food, preparing the mouth for digestion.

Acquisition

The process of acquiring or gaining knowledge, skills, or objects. In psychology, it often refers to the initial stages of learning.