ATI TEAS 7 Science 2026 Practice Test – Your All-in-One Resource for Exam Success!

Protons and neutrons are found primarily in the nucleus of the atom. The nucleus is a dense core at the center of the atom that contains these particles, which are collectively known as nucleons. Protons carry a positive charge, while neutrons have no charge. This central nucleus is crucial for defining an atom's identity and its mass, as protons contribute to the element's atomic number, while neutrons contribute to the atomic mass.

In contrast, the electron cloud surrounds the nucleus and contains electrons, which are much lighter and negatively charged. The outer shell and energy levels refer to the regions where electrons are located and indicate the distribution of these negatively charged subatomic particles as they occupy specific energy states around the nucleus. The distinction between the nucleus and the electron cloud is essential for understanding atomic structure and behavior.