Atomic Structure Basics

Think of an atom like a miniature solar system that's far too small to see. Every single thing you can touch is made up of billions of these incredible structures.

At the heart of each atom sits the nucleus - a dense core packed with protons (positive charge) and neutrons (no charge). This tiny centre contains almost all the atom's mass, even though it's incredibly small compared to the whole atom.

Whizzing around this nucleus are electrons - negatively charged particles that are roughly 1,860 times lighter than protons. These electrons don't just randomly float about; they occupy specific energy levels or shells around the nucleus, held in place by the attraction between their negative charge and the protons' positive charge.

Here's the clever bit: atoms are naturally neutral because they have equal numbers of protons $+1 charge each$ and electrons $-1 charge each$. When atoms lose or gain electrons, they become ions with either a positive charge (lost electrons) or negative charge (gained electrons).

Quick Check: If an atom loses two electrons, it becomes a +2 ion because it now has two more protons than electrons!