What do atoms in the same row have been common?

Atoms in the same row of the Periodic Table, known as a period, share the same number of electron shells. This means they have the same principal energy level, which affects their size and ionization energy. However, they differ in the number of protons and electrons, leading to variations in their chemical properties. As you move across a period from left to right, elements typically become more electronegative and exhibit increased metallic character.