How is it possible for an element to decay forward in the periodic table that is to decay to an element of higher atomic number?

Answer 1

When elements form other elements of a higher atomic number, the process by which that happens is called nuclear fusion, not radioactive decay, and it normally happens only inside stars.

Answer 2

An element can decay forward in the Periodic Table through processes like beta decay, where a neutron in the nucleus is converted into a proton, increasing the atomic number by one. This transformation results in the emission of an electron (beta particle) and an antineutrino. By changing a neutron into a proton, the element transmutes into an element with a higher atomic number.