How do atoms move from left to right in each period what do you call it?

Atoms move from left to right in each period of the Periodic Table through a process called "periodic trends." As you move across a period, the atomic number increases, leading to a greater positive charge in the nucleus. This increase in positive charge attracts electrons more strongly, resulting in a decrease in atomic radius and a change in chemical properties. The movement of atoms in this context reflects their increasing nuclear charge and electron configuration.