Chemistry is the study of the properties and behavior of matter.

It is known as matter everything that has mass and occupies space whether it is large or small.

A property is any characteristic that allows us to recognize a particular type of material and distinguish it from others.

A photograph, a ball, or the air we breathe are examples of matter, however, not all forms of matter are so common or familiar.

All experiments show that the impressive variety of forms of matter in our world is due to the combination of about 100 basic or elementary substances called chemical elements.

As we move forward we will try to relate the properties of matter with its composition, i. e. with the elements that contain and the structure, that is, the physical form in which the components are ordered.

Chemistry provides the knowledge to understand the properties of matter from atoms, the “blocks” of almost infinitesimal amount of matter.

Each element consists of a single kind of atom.

We will see that the properties of matter are related to the types of atoms that contains (composition) and their spatial arrangement (structure).

Atoms can be mixed to form molecules in which two or more atoms are bonded (linked) specifically.

Any variation we observe in our surroundings, from the boiling water to the changes that occur in our bodies against a disease, are explained at the molecular level, that is to say in the world of atoms and molecules.

As we advance in the study of chemistry, we will reason about reality and the phenomena in two ways: the macroscopic realm (with “ordinary” object size; macro = large) and the submicroscopic realm of atoms and molecules.

We do our experiments in the macroscopic world, but to understand it, we must understand the behavior of atoms and molecules at the submicroscopic level.

Chemistry is the science that seeks to explain the properties and behavior of matter by the knowledge of the properties and behavior of atoms and molecules.