Isotopes of sodium


There are 21 known isotopes of sodium, ranging from to , and five isomers. is the only stable isotope, making sodium a monoisotopic element. Sodium has two radioactive cosmogenic isotopes. With the exception of those two isotopes, all other isotopes have half-lives under a minute, most under a second.
Acute neutron radiation exposure converts some of the stable in human blood plasma to. The neutron radiation dose absorbed by the patient can be assessed by measuring the concentration of the radioisotope.
is a positron-emitting isotope with a relatively long half-life, about 2.6 years. It is used to create test-objects and point-sources for positron emission tomography.

List of isotopes

Sodium-22

Sodium-22 is a radioactive isotope of sodium, undergoing positron emission to with a half-life of 2.6019 years. is being investigated as an efficient generator of "cold positrons" to produce muons for catalyzing fusion of deuterium. It is also commonly used as a positron source in positron annihilation spectroscopy.

Sodium-23

Sodium-23 is the sole natural isotope of sodium, with an atomic mass of 22.98976928. Because of this, sodium-23 is used in nuclear magnetic resonance in various research fields, including materials science and battery research. Sodium-23 relaxation has applications in studying cation-biomolecule interactions, intracellular and extracellular sodium, ion transport in batteries, and quantum information processing.

Sodium-24

Sodium-24 is radioactive and is generally created from common sodium-23 by neutron activation. With a half-life of 14.956 hours, decays to by emission of an electron and, almost always, two gamma rays.
Exposure of the human body to intense neutron radiation creates in the blood plasma. Measurements of its quantity can be done to determine the absorbed radiation dose of a patient. This can be used to determine the medical treatment required.
When sodium is used as coolant in fast breeder reactors, radioactive is created within the coolant. When the decays, magnesium forms and builds up in the coolant. Since the half-life is short, the portion of the coolant ceases to be radioactive within a few days after removal from the reactor. Leakage of the hot sodium from the primary loop may cause radioactive fires, as it can ignite in contact with air. For this reason, the primary cooling loop is placed within the containment vessel.
Sodium has been proposed as a casing for a salted bomb, as it would convert to and produce intense gamma-ray emissions for a few days.