Radioactivity and radioactive dating
The elements with atomic number greater than 82 are radioactive.
The is a measure of how quickly on average a radioactive nuclei will take to decay.
Let's say you have 100g of uranium (don't try this at home, it’s radioactive). The half-life of uranium-238 is 4,500,000,000 years.
When 50g remain (and 50g have become something different), the amount of time that has passed is the half-life. That is a long time to wait for radioactive atoms to change, and many of the things that the original atoms change into are ALSO radioactive and dangerous!
There is even a radioactive isotope of carbon, carbon-14. C-14 has two extra neutrons and a half-life of 5730 years.
Scientists use C-14 in a process called carbon dating.
Curie · Skłodowska-Curie · Davisson · Fermi · Hahn · Jensen · Lawrence · Mayer · Meitner · Oliphant · Oppenheimer · Proca · Purcell · Rabi · Rutherford · Soddy · Strassmann · Szilárd · Teller · Thomson · Walton · Wigner Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation, such as an alpha particle, beta particle with neutrino or only a neutrino in the case of electron capture, gamma ray, or electron in the case of internal conversion.
If there are multiple particles produced during a single decay, as in beta decay, their relative angular distribution, or spin directions may not be isotropic.
Generally, elements with atomic number more than 82 show radioactivity and disintegrated to small nuclei with the emission of alpha, beta, proton, neutron particles or gamma rays.
Certain highly excited short-lived nuclear states can decay through neutron emission, or more rarely, proton emission. random) process at the level of single atoms, in that, according to quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed.
A material containing such unstable nuclei is considered radioactive.
The emission was known as m) and over this short distance it can overcome the electromagnetic repulsion between the positively charged protons.
Nuclei with radii that are within the range of the Strong force are stable.