This tutorial reviews the concept of molecular mass as the sum of the atomic masses of the atoms in a molecule. By necessity this reinforces the concept of atomic mass as the number of protons and neutrons in an atom, and in doing so reinforces the idea that atoms are composed of protons, neutrons and electrons. It is important that students understand the concept of molecular mass when studying macromolecules whose defining characteristic is extremely high molecular mass.

Relevant National Science Education Standards

Unifying Concepts and Processes — Atoms are systems of protons, electrons, and neutrons, and molecules are systems of atoms. This is reinforced in the tutorial.

Physical Science — The structure of matter on the atomic and molecular levels is central to the tutorial.