The Radioactive Isotope Tritium Decays with a First-Order Rate Constant

question 47

Multiple Choice

The radioactive isotope tritium decays with a first-order rate constant k of 0.056 year⁻¹. What fraction of the tritium initially in a sample is still present 30 years later?

• A)0.19
• B)0.60
• C)0.15
• D)2.8 × 10 ⁻³⁸
• E)None of these choices are correct.

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Definitions:

Blastopore

The opening of the central cavity of an embryo in the early stage of development, which eventually develops into the digestive tract in some animals.

Coelom

The fluid-filled body cavity between the intestinal canal and the body wall in triploblastic animals, providing space for the development of internal organs.

Protostomes

A group of animals characterized by developing the mouth before the anus during embryonic development.

Tapeworms

Parasitic flatworms that live in the digestive tracts of vertebrates, absorbing nutrients from the host's intestine.