U-235,the isotope of uranium that is essential for operating nuclear power plants,is ____________.
A) the most common of the naturally occurring isotopes of uranium
B) heavier than the other well-known isotope of uranium
C) so rare even in uranium oxide deposits that uranium ore must be processed to enrich the proportion of U-235 to all uranium
D) created by "breeder reactors" as well as produced during nuclear (atomic bomb) explosions

Question

Quizplus · Accepted Answer

U-235 is not the most common isotope of uranium, which is U-238. U-235 is slightly lighter than U-238, making B incorrect. U-235 is indeed rare, and must be extracted through enrichment processes, meaning C is correct. U-235 is also created through breeder reactors and nuclear explosions, making D partially correct, but C is the best choice as it is the most accurate and complete answer.

U-235,the Isotope of Uranium That Is Essential for Operating Nuclear