What are the properties of radioactive particles?

Answer 1

Radioactive materials have unstable nuclei. That's what makes them what they are. The nucleus of a radionuclide will eventually decay. The time that must pass before this happens, and the manner in which the decay will take place vary from one radioisotope to another. As regards the length of time to decay, we cannot know for a given atom of a radionuclide just when it will decay. Certainly we can (and do) find what is called a half-life for each radioisotope. This is a statistically arrived at "average" for the length of time it will take for a given radioisotope to "lose" half its mass to decay. While we can't know when a given atom of something will decay, we can find, and with a great deal of accuracy, the length of time it will take for half of a large number of atoms of a given radionuclide to decay. When it comes to modes of radioactive decay, there are several, and each radioisotope has one of the modes as its own (though there are a few radionuclides that have a couple of different possible decay schemes). The decay schemes are spontaneous fission, alpha decay, beta decay (several kinds), proton emission, double proton emission, neutron emission, and cluster decay. This short post hits the nail on the head. More information is certainly out there, and Wikipedia has some good stuff posted. You'll find a link below to material that is on point.