A graph of the number of neutrons versus the number of protons for all stable naturally occurring nuclei.

Nuclei that lie to the right of this band of stability are neutron poor; nuclei to the left of the band are neutron-rich.

types of archaeological dating-73types of archaeological dating-48

The reaction is usually accompanied by the ejection of one or more neutrons.

In 1934 Enrico Fermi proposed a theory that explained the three forms of beta decay.

Alpha decay of the The sum of the mass numbers of the products (234 4) is equal to the mass number of the parent nuclide (238), and the sum of the charges on the products (90 2) is equal to the charge on the parent nuclide.

Nuclei can also decay by capturing one of the electrons that surround the nucleus.

It can capture an electron or it can emit a positron.

Electron emission therefore leads to an increase in the atomic number of the nucleus.

Neutron-poor nuclides with atomic numbers less than 83 tend to decay by either electron capture or positron emission.

Many of these nuclides decay by both routes, but positron emission is more often observed in the lighter nuclides, such as A third mode of decay is observed in neutron-poor nuclides that have atomic numbers larger than 83.

This calculation helps us understand the fascination of nuclear reactions.

The energy released when natural gas is burned is about 800 k J/mol.

Alpha decay is usually restricted to the heavier elements in the periodic table.