What is the half-life of Uranium-235?

The half-life of uranium-235 (U-235) is 703,800,000 years. The half-life is the time it takes for half of a given quantity of a radioactive isotope to undergo decay and transform into a different element or isotope. U-235 is a naturally occurring radioactive isotope of uranium that undergoes radioactive decay, specifically alpha decay, where it emits an alpha particle and transforms into thorium-231. The average time it takes for half of the U-235 atoms in a sample to decay is 703,800,000 years. This value is determined experimentally and has been well-established through studies and observations in nuclear physics and radioactive dating techniques.