So now we are on to elements. Most elements are natural. They are defined as substances that cannot be broken down into any other substance. It's kinda like prime numbers. The numbers 1, 3, 5, 7, 11, and 13 cannot be divided evenly by any smaller numbers. Elements basically only consist of atoms, and are not made by combining any other substances together. Elements are what combine to create other substances.
Each atom in an element contains a specific amount of protons, which is what is used to determine the "atomic number".
If you've never heard of it, there is a chart called the Periodic Table of Elements. It lists all of the 118 known elements. There are 92 elements on the Table that are found in nature, 22 that are lab created, and 4 that are theoretical, which means they are yet to be found or created.
In the study of essential oils, it will be important to understand the atomic weights of elements, because they affect the fragrance, the consistency, and the length of time an oil has an effect on the body. The atomic weight also determines whether or not an essential oil is able to pass through the blood-brain barrier.