Which element has the lowest atomic number among Barium, Manganese, and Iron?

In order to determine which element has the lowest atomic number among Barium, Manganese, and Iron, it is essential to understand what an atomic number represents. The atomic number of an element is defined as the number of protons present in the nucleus of an atom of that element, and it uniquely identifies the element.

Iron has an atomic number of 26, which means it contains 26 protons. Manganese, on the other hand, has an atomic number of 25, indicating it has 25 protons. Barium has an atomic number of 56, reflecting that it has 56 protons.

When comparing these numbers, Manganese, with an atomic number of 25, is indeed the element with the lowest atomic number among the three, since both Iron and Barium have higher atomic numbers.

Understanding atomic numbers helps in identifying elements and understanding their positions in the periodic table, which is pivotal in chemistry and related sciences.