In its most basic form, a chemical is an element, in that it has a specific molecular composition and may be produced by or used during a natural chemical process. An element is a chemical substance made of specific kinds of atoms that cannot be broken down any further; in short, elements are the purest forms of chemicals known to man. When multiple chemicals combine, a chemical compound is formed, which exists in order to combine different types of elements, and therefore, different reactions.
Perhaps the main use of chemicals is to promote and enhance a greater quality of life for not only the human race, but countless other species as well, as they allow for the creation of modern day inventions. Anything made up of matter, or anything that is considered a solid, liquid, or gas, is made up of chemicals; this means that nearly everything a person uses throughout the day is composed of chemicals. Chemicals are used as a basic function of everyday life; they are combined in such ways as to create many commonly used substances—from the water one drinks to the gasoline that provides an automobile its energy.
Just 100 years ago, many of the chemicals being used today did not exist, at least not in a known form. This includes the chemicals needed to produce things like modern medicines and cleaning supplies. In addition to the chemicals already being used in the modern world, more chemicals are coming into existence every day.
In order to produce chemical compounds, it is first necessary to come up with a chemical formula. This formula is merely a list of atoms that includes the types of atoms and the number of those specific atoms needed to form a molecule of the substance in question. Usually, this is accomplished by listing the type of atom first, followed by the number of atoms needed for that particular compound.
For example, consider one of the most common chemical formulas known to the world H2O. This is two atoms of hydrogen combined with one atom of oxygen. The result is one of the most basic, life-sustaining chemicals known to mankind—water.
The order of elements in the formula is usually determined by the Hill system, which states that all carbon atoms will be listed first, hydrogen atoms second, then all other remaining atoms alphabetically. The exception to this is ionic compounds, which will always list the positively charged ion first. This is the case for NaCl, the formula for salt.
However, while a chemical can be a good thing, certain kinds of chemicals can also have negative effects both on people and the environment. For example, some chemicals can pose serious risks if they are ingested, some chemicals are believed to cause cancer, and some chemicals are known to be hazardous to the atmosphere. Many websites and books are devoted to educating the public about the potentially harmful side effects that can arise from chemicals.
Chemists, or those who work with chemicals, are charged with understanding how different chemicals will react with each other. Without this knowledge, it is very possible that experimenting with certain chemicals can lead to catastrophic results.
The study of chemical substances is called chemistry. Often, the most basic forms of chemistry classes begin in high school and then continue on throughout higher learning institutions. Those who need a background in chemistry include doctors, pharmaceutical researchers, and even food and synthetic food developers.