The type of radioactive decay that increases the atomic number of a radioactive atom is known as beta decay. Beta decay occurs when an unstable atom undergoes a transformation in its nucleus, resulting in the emission of a beta particle. There are two types of beta decay: beta-minus (β-) decay and beta-plus (β+) decay.
In beta-minus decay, a neutron in the nucleus of an atom is converted into a proton. The atomic number increases by one because a proton, which has a positive charge, replaces a neutron, which has no charge. The number of neutrons decreases by one, while the mass number (the sum of protons and neutrons) remains the same. As a result, the atom transitions to a different element in the periodic table with a higher atomic number.
In beta-plus decay, a proton in the nucleus of an atom is transformed into a neutron. The atomic number decreases by one as a positively charged proton is converted into a neutral neutron. The number of neutrons increases by one, while the mass number remains constant. The atom transitions to a different element with a lower atomic number.
It's important to note that radioactive decay is a random process, and not all radioactive isotopes undergo beta decay. The type of decay that occurs depends on the specific properties of the atom and the forces within its nucleus.