Definition of General Chemistry

Chemistry is a discipline scientific study in which the structure, composition and the set of properties of matter. Matter is understood as everything that exists, from what is alive to what is lifeless. It can be said, therefore, that chemistry focuses on the study of the compounds that make up matter.

In other words, chemistry deals with the nature of matter, its atomic composition, its structure, and the various states of matter.

Properties of chemical compounds

The properties of the different chemical compounds are classified into two: intensive or extensive. The first are those that do not depend on the amount of matter, that is, it does not matter volume of a substance, since its properties do not depend on this factor (the most relevant intensive properties are density, temperature or boiling point).

Extensive properties do depend on quantity, as with volume or weight (for example, a mass of 100 grams of steel than a mass of one kilogram).

Structure of matter

All matter is structured in atoms. The atom is made up of two parts: inside there is a nucleus that represents the practice totality of the mass of the atom and an external zone or electronic cloud that represents almost the totality of the volume of the atom.

Both the nucleus and its electron cloud have smaller subatomic-type particles. In the nucleus there are about 200 subatomic particles, protons and neutrons being the most relevant. In the electronic cloud are electrons, which are negatively charged particles that rotate around the nucleus.

Composition of matter

When matter is analyzed according to the different chemical substances that constitute it, it is possible to find a wide diversity material that are divided into pure substances or mixtures.

Pure substances can be classified as follows: those that are made up of a single element (for example, oxygen) or those that are formed by two or more chemical elements (for example, Water which is made up of hydrogen and oxygen).

On the other hand, mixtures of two or more than two different components are classified into two large groups according to their appearance: those mixtures whose components can be observe evenly distributed throughout the volume or those mixtures that can be distinguished with the naked eye its different substances in a material mass.

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