GCSE Chemistry - Atoms & Ions | Protons, Neutrons, Electrons (2026/27 exams)

Summary

This video introduces the basic structure of atoms, including protons, neutrons, and electrons, their relative masses and charges. It also explains how atoms can become ions and how to interpret nuclear symbols.

Highlights

The Basic Structure of an Atom00:00:06

Atoms are the tiny particles that make up everything and consist of a central nucleus surrounded by electrons orbiting in shells. The nucleus is composed of protons and neutrons.

Relative Mass and Charge of Subatomic Particles00:01:07

Protons and neutrons have a relative mass of one. Electrons are much smaller, with a mass 2,000 times less. Protons have a +1 charge, neutrons have no charge (neutral), and electrons have a -1 charge.

Size and Structure of an Atom00:02:32

The size of an atom varies by element, with a typical radius of 0.1 nanometers. Most of an atom is empty space. The nucleus is extremely small compared to the atom, about 10,000 times smaller.

Atoms Becoming Ions00:03:29

An atom is typically neutral with an equal number of protons and electrons. If an atom loses or gains electrons, it becomes charged and is then called an ion. Gaining electrons creates a negative ion, while losing electrons creates a positive ion.

Understanding Nuclear Symbols and the Periodic Table00:04:58

The periodic table contains nuclear symbols for each element. The elemental symbol (e.g., O for Oxygen) identifies the element. The atomic number (bottom left) indicates the number of protons and electrons. The mass number (top left) is the sum of protons and neutrons. The number of protons determines the element.