Start here if you want to understand what atoms actually are. This video builds the nuclear model from first principles — protons, neutrons, and electrons — and explains how their properties (mass, charge, and location) determine everything about how atoms behave. You'll also get a genuine sense of how astonishingly small and mostly empty an atom really is.

What You Will Learn

01:02What atoms are and why they are considered the fundamental building blocks of all matter.

02:45What protons are, their relative mass and charge, and where they are found in an atom.

02:49What neutrons are, their relative mass and charge, and how they differ from protons.

03:37What electrons are, their relative mass and charge, and how they are arranged around the nucleus.

04:33Why atoms are electrically neutral overall and what this tells us about proton and electron counts.

05:25How the scale of an atom compares to its nucleus and what "mostly empty space" means in practice.

09:23What holds the nucleus together and why the strong nuclear force is needed to explain atomic stability.