A radioactive isotope, also known as a radioisotope, radionuclide, or radioactive nuclide, is any of several species of the same chemical element with different masses whose nuclei are …

Dec 6, 2025 · The emissions of the most common forms of spontaneous radioactive decay are the alpha (α) particle, the beta (β) particle, the gamma (γ) ray, and the neutrino.

Dec 6, 2025 · Radium is a radioactive chemical element that is the heaviest of the alkaline-earth metals of the periodic table. Radium is a silvery white metal that does not occur free in nature.

Since only two of the transuranium elements have been found in nature (neptunium and plutonium) and those only in trace amounts, the synthesis of these elements through nuclear …

Dec 5, 2025 · Plutonium (Pu), radioactive chemical element of the actinoid series of the periodic table, atomic number 94. It is the most important transuranium element because of its use as …

Physical science - Radioactivity, Transmutation, Elements: The discovery of radioactivity by the French physicist Henri Becquerel in 1896 is generally taken to mark the beginning of 20th …

All of its isotopes are radioactive. For chemical research, curium-242 (163-day half-life) has been supplanted by curium-244 (18.1-year half-life) and the still longer-lived isotope curium-248, …

Three chemical elements were first discovered in pitchblende: uranium by the German chemist Martin Klaproth in 1789, and polonium and radium by the French scientists Pierre and Marie …

Dec 13, 2025 · It is now known that uranium, radioactive in all its isotopes, consists naturally of a mixture of uranium-238 (99.27 percent, 4,510,000,000-year half-life), uranium-235 (0.72 …

Jan 7, 2026 · More than 30 radioactive isotopes have been reported. Of the radioactive isotopes of lead, the following appear as members of the three natural decay series: (1) thorium series: …