Many radioactive atoms that have large masses undergo radioactive decay by releasing a particle that is identical to a helium - 4 nucleus. What charges in the original atom are expected as a result of this phenomenon

Many heavy radioactive atoms release alpha particles which are identical to helium-4 atoms. It is expected that emission of alpha particle will decrease the number of electrons and the original atom obtains positive charge. However, emission of one alpha particle decreases the atomic number of the original atom by 2 and the mass number decreases by 4. This is because atomic number of helium atom is 2 and the mass number is 4. As a result a new atom is formed. This is the product of the radioactive reaction.