A Sample Contains 1000 Nuclei of a Radioactive Isotope of Barium

question 30

Multiple Choice

A sample contains 1000 nuclei of a radioactive isotope of barium. Exactly sixty seconds later, 970 nuclei in the sample have decayed. Determine the half-life of this isotope.

• A)10 s
• B)12 s
• C)14 s
• D)16 s
• E)18 s

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Definitions:

Molybdenum

A chemical element with the symbol Mo and atomic number 42, essential for most organisms as a trace dietary mineral.

Electron Transport

A series of reactions that transfer electrons from electron donors to electron acceptors via redox reactions, coupled with the transfer of protons across a membrane.

Zinc

Zinc is a metallic element essential for human health, involved in numerous aspects of cellular metabolism, immune function, and as a cofactor for over a hundred enzymes.

Copper

A reddish-brown metal with high electrical and thermal conductivity, widely used in electrical wiring and in alloying.