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How much uranium-235 is found in natural uranium?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — actinoid element Modern version of the periodic table of the elements (printable).

In naturally occurring uranium, uranium-235 constitutes approximately 0.72 percent of the total composition. The vast majority of natural uranium consists of the isotope uranium-238, which makes up about 99.27 percent, while a very small fraction (0.006 percent) is uranium-234.12