When is an isotope unstable

The nucleus of each atom contains protons and neutrons. While the number of protons defines the element e. Stable isotopes do not decay into other elements. In contrast, radioactive isotopes e. The less abundant stable isotope s of an element have one or two additional neutrons than protons, and thus are heavier than the more common stable isotope for those elements.

Because its nucleus has reached critical mass and the core charge and forces holding the atom together is not strong enough to contain the large nucleus size, it undergoes beta decay. There could be other factors that affect the stability of an atom but I know this is one of them. What is the difference in stable and unstable isotopes? Chemistry Matter Isotopes. Jun 14, Nucleus Mass. Explanation: Usually, what makes an isotope unstable is the large nucleus.

This technique is called radiocarbon dating, or carbon dating for short. Other elements have isotopes with different half lives. For example, 40 K potassium has a half-life of 1. Scientists often use these other radioactive elements to date objects that are older than 50, years the limit of carbon dating. Through the use of radiometric dating, scientists can study the age of fossils or other remains of extinct organisms.

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Atoms, Molecules, and Ions. Search for:. Learning Objective Discuss the properties of isotopes and their use in radiometric dating. Key Points Isotopes are atoms of the same element that contain an identical number of protons, but a different number of neutrons. Despite having different numbers of neutrons, isotopes of the same element have very similar physical properties. Some isotopes are unstable and will undergo radioactive decay to become other elements.