Isotope | Examples & Definition | Britannica
网页2024年9月26日 · isotope, one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behaviour but with different atomic masses and physical properties. Every chemical element has one or more isotopes.
Isotope - Discovery, Radioactivity, Elements | Britannica
网页2024年9月26日 · A uniform scale of nuclear stability, one that applies to stable and unstable isotopes alike, is based on a comparison of measured isotope masses with the masses of their constituent electrons, protons, and neutrons. For this purpose, electrons and protons are paired together as hydrogen atoms.
Radioactive isotope | Description, Uses, & Examples | Britannica
网页radioactive isotope, any of several species of the same chemical element with different masses whose nuclei are unstable and dissipate excess energy by spontaneously emitting radiation in the form of alpha, beta, and gamma rays. A brief treatment of radioactive isotopes follows.
isotope - Students | Britannica Kids | Homework Help
网页An isotope is one of two or more types of atoms of a chemical element with the same number of protons but with different numbers of neutrons and therefore different atomic masses. Every chemical element has one or more isotopes. The isotopes of an element occupy the same position in the periodic table.
Tritium | Radioactive, Hydrogen, Decay | Britannica
网页2024年9月26日 · Tritium, (T, or 3H), the isotope of hydrogen with atomic weight of approximately 3. Its nucleus, consisting of one proton and two neutrons, has triple the mass of the nucleus of ordinary hydrogen. Tritium is a radioactive species having a half-life of 12.32 years; it occurs in natural water with an.
Geology - Isotopes, Geochemistry, Rocks | Britannica
网页2024年10月4日 · Isotopic geochemistry has several principal roles in geology. One is concerned with the enrichment or impoverishment of certain isotopic species that results from the influence of differences in mass of molecules containing different isotopes. Measurements of the proportions of various isotopic species can be used as a form of …
Isotope Definition & Meaning | Britannica Dictionary
网页ISOTOPE meaning: any one of various forms in which the atoms of a chemical element can occur.
Carbon-12 | isotope | Britannica
网页In carbon. In 1961 the isotope carbon-12 was selected to replace oxygen as the standard relative to which the atomic weights of all the other elements are measured. Carbon-14, which is radioactive, is the isotope used in radiocarbon dating and radiolabeling. Read More.
Nuclear fission | Examples & Process | Britannica
网页2024年9月28日 · Nuclear fission, subdivision of a heavy atomic nucleus, such as that of uranium or plutonium, into two fragments of roughly equal mass. The process is accompanied by the release of a large amount of energy.
isotope dilution - Encyclopedia Britannica
网页Isotope dilution, radiochemical method of analysis for measuring the mass and quantity of an element in a substance. The procedure involves adding to a substance a known quantity of a radioisotope of the element to be measured and mixing it …