1.2: Chemicals Compose Ordinary Things
Chemistry is the branch of science dealing with the structure, composition, properties, and the reactive characteristics of matter. Matter is anything that has mass and occupies space. Thus, chemistry is the study of literally everything around us – the liquids that we drink, the gasses we breathe, the composition of everything from the plastic case on your phone to the earth beneath your feet. Moreover, chemistry is the study of the transformation of matter. Crude oil is transformed into more useful petroleum products such as gasoline and kerosene by the process of refining. Some of these products are further transformed into plastics. Crude metal ores are transformed into metals, that can then be fashioned into everything from foil to automobiles. Potential drugs are identified from natural sources, isolated and then prepared in the laboratory. Their structures are systematically modified to produce the pharmaceuticals that have led to vast advances in modern medicine. Chemistry is at the center of all of these processes and chemists are the people that study the nature of matter and learn to design, predict and control these chemical transformations. Within the branches of chemistry you will find several apparent subdivisions. Inorganic chemistry, historically, focused on minerals and metals found in the earth, while organic chemistry dealt with carbon-containing compounds that were first identified in living things. Biochemistry is an outgrowth of the application of organic chemistry to biology and relates to the chemical basis for living things. In the later chapters of this text we will explore organic and biochemistry in a bit more detail and you will notice examples of organic compounds scattered throughout the text. Today, the lines between the various fields have blurred significantly and a contemporary chemist is expected to have a broad background in all of these areas.
In this chapter we will discuss some of the properties of matter, how chemists measure those properties and we will introduce some of the vocabulary that is used throughout chemistry and the other physical sciences.
Let’s begin with matter. Matter is defined as any substance that has mass. It’s important to distinguish here between weight and mass. Weight is the result of the pull of gravity on an object. On the Moon, an object will weigh less than the same object on Earth because the pull of gravity is less on the Moon. The mass of an object, however, is an inherent property of that object and does not change, regardless of location, gravitational pull, or whatever. It is a property that is solely dependent on the quantity of matter within the object.
Contemporary theories suggests that matter is composed of atoms . Atoms themselves are constructed and characterized from the subatomic particles called neutrons, protons and electrons that the atom possesses. Atoms will be studied closer in chapter 4 of this text. There are at least 116 different types of atoms recognized by scientists today, each type having a different number of protons in its nucleus. These different types of atoms are called elements .
As different elements were discovered and named, abbreviations of their names were developed to allow for a convenient chemical shorthand. The abbreviation for an element is called its chemical symbol. A chemical symbol consists of one or two letters, and the relationship between the symbol and the name of the element is generally apparent. Thus helium has the chemical symbol He, nitrogen is N, and lithium is Li. Sometimes the symbol is less apparent but is decipherable; magnesium is Mg, strontium is Sr, and manganese is Mn. Symbols for elements that have been known since ancient times, however, are often based on Latin or Greek names and appear somewhat obscure from their modern English names. For example, copper is Cu (from cuprum), silver is Ag (from argentum), gold is Au (from aurum), and iron is (Fe from ferrum). Throughout your study of chemistry, you will routinely use chemical symbols and it is important that you begin the process of learning the names and chemical symbols for the common elements. By the time you complete this course, you should be able to name and identify the symbols for common elements. Table \(\PageIndex{1}\) contains a starter list of common elements that you should begin learning now, as they will be the ones you are expected to know for this course.
| Element | Chemical Symbol | Element | Chemical Symbol |
|---|---|---|---|
| Aluminum | Al | Gold | Au |
| Beryllium | Be | Argon | Ar |
| Boron | B | Potassium | K |
| Carbon | C | Calcium | Ca |
| Fluorine | F | Zinc | Zn |
| Helium | He | Sulfur | S |
| Hydrogen | H | Phosphorus | P |
| Lithium | Li | Chlorine | Cl |
| Magnesium | Mg | Iodine | I |
| Manganese | Mn | Arsenic | As |
| Mercury | Hg | Barium | Ba |
| Neon | Ne | Bromine | Br |
| Nitrogen | N | Iron | Fe |
| Oxygen | O | Copper | Cu |
| Silicon | Si | Lead | Pb |
| Sodium | Na | Silver | Ag |
| Tin | Sn | Chromium | Cr |
Contributions & Attributions
This page was constructed from content via the following contributor(s) and edited (topically or extensively) by the LibreTexts development team to meet platform style, presentation, and quality:
-
Paul R. Young , Professor of Chemistry, University of Illinois at Chicago, Wiki: AskTheNerd; PRY askthenerd.com - pyoung uic.edu; ChemistryOnline.com
-
Henry Agnew (UC Davis)