Isotopes with unstable nuclei are 1 and are called 2. The 3 of radioisotopes decay to 4nuclei plus emission of large amounts of 5 . The radiation may be alpha, 6, or gamma. 7 radiation consists of alpha particles (positively charged 8 nuclei) that are easily stopped by a sheet of paper. Beta radiation is composed of fast-moving particles, which are 9. Beta radiation is more penetrating than alpha radiation; it is stopped by 10. 11 radiation is electromagnetic radiation. Gamma radiation has no 12 or electrical charge. It is extremely penetrating. 13 bricks and 14 reduce the intensity of gamma radiation but do not completely 15 it.

Isotopes are radioactive with unstable nuclei, called radioisotopes.
Radioisotopes' cores decay into the stable core, with enormous quantities of radiation emissions.
It could be either alpha, beta, or gamma.
Alpha radiation is made up of alpha particles, that are easy to halt with such a piece of paper.
Beta spread spectrum of quickly shifting, electrical electrons.
Beta radiation permeates upwards of alpha radiation; metal foil gets halted.
Electromagnetic radiation is gamma energy.
There is also no electrical or mass radiation. It's also quite insightful.
Lead brick and concrete lessen, but just don't stop, the strength of gamma radiation.