What series of inner transitional metals includes atomic numbers from 90 to 103?

The series of inner transitional metals that includes atomic numbers from 90 to 103 is the Actinide series. This series consists of elements that are characterized by their filling of the 5f orbital. The actinides include well-known elements such as uranium and plutonium, which are significant in both nuclear chemistry and applications, particularly in energy and weaponry.

Understanding the classification of these elements is crucial in chemistry. The lanthanide series, for example, encompasses elements with atomic numbers from 57 to 71 and fills the 4f orbital. The noble gases, known for their lack of reactivity, include elements such as helium and neon, while transition metals are primarily located in the d-block of the periodic table. Each of these groupings has distinct properties and electron configurations, highlighting the importance of recognizing the characteristics that differentiate them.