A Pure Sample of Tritium, ³H, Was Prepared and Sealed

question 59

Multiple Choice

A pure sample of tritium, ³H, was prepared and sealed in a container for a number of years. Tritium undergoes  decay with a half-life of 12.32 years. How long has the container been sealed if analysis of the contents shows there are 5.25 mol of ³H and 6.35 mol of ³He present?

• A) 2.34 y
• B) 3.38 y
• C) 9.77 y
• D) 14.1 y
• E) 25.6 y

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Definitions:

Cognitive Development

The process of growth and change in intellectual abilities, including thinking, reasoning, problem-solving, and understanding complex concepts.

Fine Motor Skills

The ability to use small muscle groups for detailed movements, such as writing or buttoning.

Centration

The tendency to focus on one part of a stimulus, situation, or idea and exclude all others; a characteristic of preoperational reasoning.

Egocentrism

A cognitive characteristic where an individual has difficulty understanding or considering perspectives other than their own, prevalent in early childhood.