1.2 Atomic Structure

Knowing the structure of atoms is key to understanding how the world works

This chapter covers

• The history of how the atomic structure was discovered; and
• Protons, neutrons and electrons.

I hope you enjoy the content - any questions, do post below in the comments box!

1.2.1 Protons, neutrons and electrons

There are three particles that make up an atom and each of them has different properties we need to know

For each type of particle, we need to know about the:

• Location;
• Charge;
• Mass; and
• What changing their number does to an atom.

We will also cover how atoms are notated in the periodic table with their atomic and mass numbers!

1.2.2 The history of the atom

It was not always known what atoms were or if they were made up of anything smaller

This chapter will take you through the history which has five pictures of what scientists thought atoms were:

• Scientists originally thought atoms were solid spheres that could not be broken down into anything smaller;
• Plumb Pudding Model: scientists thought atoms were mainly positive, with tiny negative 'raisins' which could be knocked out;
• Nuclear Model: scientists discovered that atoms had a small positive nucleus with electrons circling the perimeter;
• Bohr Model: scientists discovered that electrons have to sit in certain energy shells;
• Neutron discovery: finally scientists discovered the neutron and the masses of atoms finally made sense.