What happens to an atom when the atomic mass number changes and the atomic number stays the same ?

Nuclear decay changes the number of protons in the nucleus of an atom, and in doing so changes the element. For example, the alpha decay of uranium-235 to 231 and from 92 to 90. This gives rise to the formation of a new element- thorium-231.

Hope it helps pls mark branliest if so

The answer should be vaporization 

Deposition is the transition of matter going from gas to solid without passing through the liquid phase.a.) gas—-> solid