Some elements are radioactive - Leaving Cert Chemistry - Question (b) - 2021

The term "radioactive" refers to the property of certain elements to emit radiation as a result of the decay of their atomic nuclei. This process occurs when unstable isotopes transition to a more stable form by releasing energy in the form of radiation, which can include alpha particles, beta particles, or gamma rays.

This decay process not only changes the element into another element or isotope but may also release particles that can affect surrounding matter. The rate of decay is characterized by the half-life, which is the time required for half of the radioactive atoms in a sample to decay.

Some common examples of radioactive elements include Uranium, Polonium, and Radon, each with distinct applications and safety concerns due to their ability to emit ionizing radiation.