Here's a breakdown:
* Radioactive decay: U-235 is a radioactive isotope, meaning its nucleus is unstable and will spontaneously transform into a different element over time. This process releases energy, primarily in the form of alpha particles (helium nuclei).
* Half-life: The time it takes for half of the original U-235 atoms in a sample to decay is known as its half-life.
* Exponential decay: Radioactive decay happens at a constant rate, meaning the number of atoms decaying is proportional to the number of atoms remaining. This results in an exponential decay curve.
The half-life of Uranium-235 is approximately 703.8 million years. This means that after 703.8 million years, a sample of U-235 will have only half of its original amount remaining, and the rest will have decayed into other elements.
Implications:
* Dating: Half-life is used in radioactive dating to determine the age of ancient objects.
* Nuclear energy: U-235 is a key component in nuclear fission reactors. Its long half-life means it provides a steady source of energy.
* Radioactive waste: The long half-life of U-235 contributes to the challenges of managing radioactive waste.
Key Points:
* Half-life is a characteristic property of a radioactive isotope.
* It describes the time it takes for half of the atoms to decay.
* Half-life is constant and independent of the initial amount of the isotope.
* It is a crucial concept in understanding radioactive decay and its applications.
