What Is a Half-Life

question 54

Multiple Choice

What is a half-life ?

• A) It is a special case when the rate constant equals one-half. (i.e., k = 0.5)
• B) A period of time required for the concentration of a reactant to reduce to one-half its original value.
• C) It is a rate law that is one-half order: (i.e., Rate = k [A]^1/2)
• D) A period representing one-half the amount of time required for an initial concentration of a reactant to reduce to 0.00 M.
• E) A period representing the amount of time required for an initial concentration of a reactant to reduce to 0.5 M.

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Definitions:

Phobic Disorder

An anxiety disorder characterized by an intense, irrational fear of specific objects, activities, or situations leading to avoidance behavior.

Somatoform Disorder

Mental disorders characterized by physical symptoms without a clear physical cause, where symptoms are thought to be the manifestation of psychological conflicts or distress.

Conversion Reaction

A psychological response where emotional distress is expressed through physical symptoms.

Irrational Fear

A fear that is disproportionate to the actual danger posed, often a symptom of anxiety disorders.