The time it takes for half of the atoms in an isotope to decay is called

When atom decays, two or more forms of the same element are obtained. These forms are called isotopes and they have the same number of protons but a different number of neutrons in relation to the parent atom. So they differ in the relative atomic mass, which is the number of core particles, while the chemical properties remain the same as the parent atom. This process takes place with radioactive decays where radioactive isotopes are obtained, and the time required for decay is half life, and this is the time that is needed for half atom parent to decay and form the daughter elements.

ayatollah khomeini can best be described as the leader who declared iran to be an islamic republic.