What happens to alpha particles when they are emitted from heavy nuclei?

When alpha particles are emitted from heavy nuclei during radioactive decay, they consist of two protons and two neutrons. This composition is identical to that of a helium nucleus, which is why this answer is correct. The emission of an alpha particle reduces the atomic number of the original nucleus by two and the mass number by four, resulting in the formation of a new element that is located two places to the left on the periodic table.

Alpha particles are relatively heavy and carry a positive charge, which is why they are not neutral or harmless. They do not gain mass or energy after emission; instead, they carry away energy as kinetic energy from the parent nucleus. Alpha particles cannot penetrate skin effectively, as they are stopped by just a few centimeters of air or the outer layer of human skin.

Understanding the nature of alpha particles helps in the field of nuclear physics and radiation safety, as their behavior and potential interactions with matter are essential in evaluating the risks associated with radioactive materials.