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What happens when an unstable atomic nucleus decays?

What happens when an unstable atomic nucleus decays?

The unstable nucleus of radioactive atoms emit radiation. When this occurs, a new atom and element are formed. This process is called radioactive decay. It continues until the forces in the unstable nucleus are balanced.

What happens when a nucleus is unstable?

Too many neutrons or protons upset this balance disrupting the binding energy from the strong nuclear forces making the nucleus unstable. An unstable nucleus tries to achieve a balanced state by given off a neutron or proton and this is done via radioactive decay.

What happens when an unstable nucleus decays by emitting a beta particle?

Beta decay occurs when, in a nucleus with too many protons or too many neutrons, one of the protons or neutrons is transformed into the other. However within a nucleus, the beta decay process can change a proton to a neutron. An isolated neutron is unstable and will decay with a half-life of 10.5 minutes.

Why is a heavy nucleus unstable?

In heavy nuclei, the Coulomb energy of proton repulsion becomes very significant and this makes the nuclei unstable. It turns out that it is energetically more profitable for a nucleus to throw out a stable system of four particles, i.e., an alpha particle, than individual nucleons.

Can’t predict when an unstable nucleus will decay?

Even if a nucleus is unstable, there is no way to tell whether it will decay in the next instant, or in millions of years’ time. However, even tiny pieces of material contain very many atoms . The half-life of a radioactive isotope is the time taken for half the unstable nuclei in a sample to decay.

What causes a nucleus to be stable?

An atom is stable if the forces among the particles that makeup the nucleus are balanced. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. Instability of an atom’s nucleus may result from an excess of either neutrons or protons.

What is the stability of a nucleus dependent on?

The stability of an atom depends on the ratio of its protons to its neutrons, as well as on whether it contains a “magic number” of neutrons or protons that would represent closed and filled quantum shells. These quantum shells correspond to energy levels within the shell model of the nucleus.

What causes a nucleus to be unstable?

What does it mean when a nucleus is unstable?

This is called radioactive decay. and randomly. This means that the process of radioactive decay can not be speeded up or slowed down by artificial means (spontaneous decay). It also means that we cannot tell when a particular unstable nucleus will decay (random decay). Some nuclei are unstable.

What happens to a nucleus during alpha decay?

Alpha decay occurs when a nucleus is unstable because it has too many protons. The nucleus emits an alpha particle and energy. An alpha particle consists of two protons and two neutrons, which is actually a helium nucleus. Losing the protons and neutrons makes the nucleus more stable.

What happens when there are too many neutrons in a nucleus?

However as the number of protons increases, more neutrons are needed to keep the nucleus stable. For example lead, lead-206 has 82 protons and has 124 neutrons. Nuclei with too many, or too few, neutrons do exist naturally but are unstable and will disintegrate (or decay) by emitting radiation. This is called radioactive decay.

How is the mass of an atom affected by radioactive decay?

Alpha decay is one type of radioactive decay, in which an atomic nucleus emits an alpha particle, and thereby transforms (or “decays”) into an atom with a mass number decreased by 4 and atomic number decreased by 2.