यूरेनियम

Uranium is a naturally occurring silvery-grey metal that is radioactive, meaning its atoms gradually break down over time by releasing particles—a process that happens at different rates for different forms of uranium, with some taking billions of years to decay. Because of these different decay rates, uranium is useful for scientists to determine the age of the Earth, and uranium-235 and uranium-238 are the most common forms found in nature.

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