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Chemistry, as we all know, is the science of matter. You should already be familiar with concepts like substances, elements, compounds, molecules, and other such lovely terms.

Ever wondered though, what are all these things made of?

Let's use Lego® as an example. I have a nice house made of Lego® pieces. Now, if I break down this house, I'll have walls and windows and a door. I can break down these further, and even further, until I get an individual, smallest piece of Lego® that still retains the properties of the house (in this case, colour and texture).

Does this work in nature? And if so, who thought of it?

Introducing-Atomic Theory:

Atomic theory is a theory that attempts to answer that question. It states that all matter is composed out of extremely small particles called atoms. An atom is the smallest particle that retains the properties of an element (so a carbon atom would still have the properties of carbon, but if you break the atom down these properties will disappear).

This theory, although it sounds simple, is in reality extremely complex. It eliminated the notion that matter like water would never stop being water no matter how small a quantity of it you have. Although it's still only a theory, nowadays, it is widely accepted and supported by virtually everyone.

And like most theories, the atomic theory has great story and history behind it.

Meet Democritus: Like most modern science, the atomic theory started in Ancient Greece (which explains the stupid names of things). The guy who thought it all up was known as Democritus, a materialist philosopher, in the 5th century BCE . He thought very hard about matter and the universe, and came up with an idea. Democritus stated that all matter is made up of units that move around in a void. Democritus believed that these units are indivisible and unchangeable. In fact, he decided to call them atomos, which means uncuttable in Greek. Although these atomos are all made up of the same matter, their shape, size, and orientation in space explains the existence of different substances and materials.

While most of Democrtius's ideas aren't acceptable today (atoms are divisible into smaller units, and they are in cnostant change), the revolutionary thought that matter is composed of tiny particles moving in a void is accepted today as the basis for modern atomic theory.

Meet Kanada: The Greek weren't the only smart guys around. In India, during the 6 century BCE, was a guy named Kanada. He founded the Vaisheshika school of philosophical thought, which came up with its own atomic theory independently of Democritus. The idea was that matter was made of a finite number of paramāṇus, which are basically atoms, indivisible and eternal. Each type of atom has its own unique individuality. Atoms make up the 4 bhūtas- water, fire, earth and air, which make up all other matter. They had various theories about how these atoms combine, and believed the interactions are ultimately caused by the will of Ishvara, a Hindu god. Again, while some of these theories aren't generally accepted today, the general ideas are there for the tiny particles that make up matter.

What happened next?

For a long time, nothing. People had more important things to do than think about matter (mostly fight wars and try to survive the hard life of the Middle Ages). Although some alchemists existed, trying to turn stuff to gold and create an immortality potion, they weren't too concerned about atoms.

And so, for hundreds of years, nobody cared, and atomic theory wasn't explored. People either accepted the notion that matter can be divided into infinitely small amounts without a change in properties, or that there's something that makes up matter, but since nobody could really check it made no difference.

Until one day, in the early 1800s, an English guy name John Dalton changed everything…

Continue reading History of Atomic Theory II.