[Answer] After a radioactive atom decays it is the same element that it was before with no measurable change in mass. Which kind of decay has occurred and how do you know?

Answer: gamma decay because photons have no mass

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After a radioactive atom decays it is the same element that it was before with no measurable change in mass. Which kind of decay has occurred and how do you know? Radioactive decay (also known as nuclear decay radioactivity radioactive disintegration or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation.A material containing unstable nuclei is considered radioactive .Three of the most common types of decay are alpha decay beta decay and gamma decay all of which involve emitting one or more particles ... decay where energy is used to convert a proton into a neutron a positron (e +) and an electron neutrino (ν e) is emitted: From known β + decay : Energy + p → n + e + + ν e. In the Cowan and Reines experiment instead of an outgoing neutrino you have an incoming antineutrino (ν e) from a nuclear reactor: Energy (> 1.8 MeV) + p + ν e ... Nuclear fission - Wikipedia Alpha decay or α- decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or ' decays into a different atomic nucleus with a mass number that is reduced by four and an atomic number that is reduced by two. An alpha particle is identical to the nucleus of a helium-4 atom which consists of two protons and two neutrons. In nuclear physics and nuclear chemistry nuclear fission is a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into two or more smaller lighter nuclei.The fission process often produces gamma photons and releases a very large amount of energy even by the energetic standards of radioactive decay .. Nuclear fission of heavy elements was discovered on ... Nuclear fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast so called because it "falls out" of the sky after the explosion and the shock wave has passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon...

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