What makes isotopes different

Chapter 1 Chapter 1: The Chemical World 1. All atoms of the same element have the same number of protons, but some may have different numbers of neutrons. For example, all carbon atoms have six protons, and most have six neutrons as well. But some carbon atoms have seven or eight neutrons instead of the usual six.

Atoms of the same element that differ in their numbers of neutrons are called isotopes. Many isotopes occur naturally. Usually one or two isotopes of an element are the most stable and common. Different isotopes of an element generally have the same physical and chemical properties because they have the same numbers of protons and electrons.

Hydrogen is an example of an element that has isotopes. Most hydrogen atoms have just one proton, one electron, and lack a neutron. These atoms are just called hydrogen. Some hydrogen atoms have one neutron as well. These atoms are the isotope named deuterium. Other hydrogen atoms have two neutrons.

These atoms are the isotope named tritium. For most elements other than hydrogen, isotopes are named for their mass number. These atoms are the isotope called carbon A lithium atom contains 3 protons in its nucleus irrespective of the number of neutrons or electrons. Notice that because the lithium atom always has 3 protons, the atomic number for lithium is always 3. The mass number, however, is 6 in the isotope with 3 neutrons, and 7 in the isotope with 4 neutrons.

In nature, only certain isotopes exist. For instance, lithium exists as an isotope with 3 neutrons, and as an isotope with 4 neutrons, but it doesn't exist as an isotope with 2 neutrons or as an isotope with 5 neutrons. They are important in nuclear medicine, oil and gas exploration, basic research, and national security. Isotopes are needed for research, commerce, medical diagnostics and treatment, and national security.

However, isotopes are not always available in sufficient quantities or at reasonable prices. The program produces and distributes radioactive and stable isotopes that are in short supply, including byproducts, surplus materials, and related isotope services.

The program also maintains the infrastructure required to produce and supply priority isotope products and related services. Finally, it conducts research and development on new and improved isotope production and processing techniques.

Scientific terms can be confusing. DOE Explains offers straightforward explanations of key words and concepts in fundamental science. As it turns out, this question is a complex one, but lends some truth to the adage that we are all made of star dust. Some of the lighter isotopes were formed very early in the history of the universe, during the Big Bang. Others result from processes that happen within stars or as a result of chance collisions between highly energetic nuclei - known as cosmic rays - within our atmosphere.

Most naturally existing isotopes are the final stable or long-lived product resulting from a long series of nuclear reactions and decays. In most of these cases, light nuclei have had to smash together with enough energy to allow the strong force - a glue-like bond that forms when protons and neutrons get close enough to touch - to overcome the electromagnetic force — which pushes protons apart.

If the strong force wins out, the colliding nuclei bind together, or fuse, to form a heavier nucleus. Our sun is a good example of this. One of its main sources of power is a series of fusion reactions and beta decay processes that transform hydrogen into helium. Since the early s, when the existence of isotopes was first realised, nuclear physicists and chemists have been seeking out ways to study how isotopes can be formed, how they decay, and how we might use them.

As it turns out, the nature of isotopes — their chemical uniformity, their nuclear distinctiveness — makes them useful for a wide range of applications in fields as diverse as medicine, archaeology, agriculture, power generation and mining. If you have ever had a PET scan , you have benefited from a byproduct of the radioactive decay of certain isotopes often called medical isotopes.

We produce these medical isotopes using our knowledge of how nuclear reactions proceed, with the help of nuclear reactors or accelerators called cyclotrons. But we have also found ways to make use of naturally occurring radioactive isotopes. Carbon dating , for example, makes use of the long-lived isotope carbon to determine how old objects are. Under normal circumstances, carbon is produced in our atmosphere via cosmic ray reactions with nitrogen It has a half-life of roughly 5, years, which means that half of a quantity of carbon will have decayed away in that time period.

While a biological organism is alive, it takes in approximately one carbon isotope for every trillion stable carbon isotopes and the carbon to carbon ratio stays about the same while the organism lives.