2025年1月18日 · An isotope is 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 …

isotope , One of two or more species of atoms of a chemical element having nuclei with the same number of protons but different numbers of neutrons. They have the same atomic number and …

2024年12月11日 · All chemical elements have many isotopes. It is usual to characterize different isotopes by giving the sum of the number of protons and neutrons in the nucleus—a quantity …

2025年1月18日 · First, the lighter isotopes, those of hydrogen and helium, constitute more than 98 percent of the mass; heavier isotopes make up scarcely 2 percent. Second, apart from the …

2025年1月18日 · Isotope - Discovery, Radioactivity, Elements: Evidence for the existence of isotopes emerged from two independent lines of research, the first being the study of …

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 …

Oxygen group element - Isotopes, Atomic Mass, Properties: The known isotopes of each of the Group 16 elements are listed in the Table. Consistent with a generality observed throughout …

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 …

2025年1月18日 · Many methods have therefore been developed to separate the isotopes of an element from one another. Each method is based on some difference—sometimes a very …

2025年1月18日 · Physical and/or chemical processes affect differently the isotopes of an element. When the effect is systematic, increasing or decreasing steadily as mass number increases, …