Tritium Is Radioactive and Decays by a First Order Process

question 65

Multiple Choice

Tritium is radioactive and decays by a first order process with a half-life of 12.5 yr. If an experiment starts with 1.00×10 ^{- 6} mol of tritium, how much is left after 4.5 yr.?

• A) 1.1×10 ^{- 7} mol
• B) 7.8×10 ^{- 7} mol
• C) 3.6×10 ^{- 7} mol
• D) 4.8×10 ^{- 6} mol
• E) 1.0×10 ^{- 9} mol

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Definitions:

Proximal Convoluted Tubule

The proximal convoluted tubule is part of the nephron in the kidney, playing a crucial role in the reabsorption of water, ions, and nutrients back into the bloodstream.

Glucose Reabsorption

The process by which the kidneys filter glucose from urine back into the bloodstream.

Microvilli

Small, finger-like projections on the surface of some cell types which increase the surface area for absorption or secretion.

Vasa Recta

A network of blood vessels in the kidney that maintains the concentration gradient required for urine concentration and regulation.