In chemistry, the smallest parts of elements that possess the characteristics of those elements are called what?

The smallest parts of elements that possess the characteristics of those elements are called atoms. Atoms are the fundamental building blocks of matter and make up all substances. Each element on the periodic table is defined by its specific type of atom, which consists of protons, neutrons, and electrons. The properties of the element, such as its reactivity, state of matter, and atomic behavior, are determined by the arrangement and number of these subatomic particles within the atom.

Molecules, on the other hand, are formed when two or more atoms bond together. Ions are atoms that have gained or lost electrons, resulting in a positive or negative charge. Radicals, often in the context of organic chemistry, are atoms or molecules that contain unpaired electrons and are generally highly reactive. While these terms are related to the study of chemistry, they do not define the fundamental unit of an element itself, which is the atom.