In some atoms<span>, the required energy is not sturdy enough to hold the </span>nucleus<span> together, and the </span>nuclei<span> of these </span>atoms<span> are said to be </span>fractionable<span>. </span>Weak atoms will<span> lose neutrons and protons as they attempt to become </span>stable<span>. In this way, atoms need that required energy.
A stable atom is an atom that has enough binding energy to hold the nucleus together permanently. An unstable atom does not have enough binding energy to hold the nucleus together permanently and is called a radioactive atom.