![]() For example, many elements conduct heat and electricity well, whereas others are poor conductors. While many elements differ dramatically in their chemical and physical properties, some elements have similar properties. The elements that exist as diatomic molecules are hydrogen (H 2), oxygen (O 2), nitrogen (N 2), fluorine (F 2), chlorine (Cl 2), bromine (Br 2), and iodine (I 2). In representing a diatomic molecule, we use the symbol of the element and include the subscript 2 to indicate that two atoms of that element are joined together. Some elements, however, exist as groups of atoms called molecules, as discussed in Chapter 1 “Atoms and Molecules.” Several important elements exist as two-atom combinations and are called diatomic molecules. For example, a macroscopic chunk of iron metal is composed, microscopically, of individual atoms. Most elements in their pure form exist as individual atoms. The closeness is even more apparent in pronunciation than in spelling. For example, gold is oro in Spanish and or in French (close to the Latin aurum), tin is estaño in Spanish (compare to stannum), lead is plomo in Spanish and plomb in French (compare to plumbum), silver is argent in French (compare to argentum), and iron is fer in French and hierro in Spanish (compare to ferrum). ElementĮlement names in languages other than English are often close to their Latin names. ![]() The following table lists the names and symbols of some common elements. The symbol Hg represents the element mercury regardless of the amount it could represent one atom of mercury or a large amount of mercury. We use the same symbol to indicate one atom of mercury (microscopic domain) or to label a container of many atoms of the element mercury (macroscopic domain). It is derived from mercury’s Latin name, hydrargyrum. Some elements have symbols that derive from earlier, mostly Latin names, so the symbols may not contain any letters from the English name.įor example, the symbol for mercury is Hg. The first letter of the symbol is usually the first letter of the element’s name, while the second letter is some other letter from the name. By convention, the first letter of a chemical symbol is a capital letter, while the second letter (if there is one) is a lowercase letter. Therefore, each element name is abbreviated as a one- or two-letter chemical symbol. The names of the elements can be cumbersome to write in full, especially when combined to form the names of compounds. Today, the names for newly discovered elements are proposed by their discoverers but must be approved by the International Union of Pure and Applied Chemistry (IUPAC), an international organization that makes recommendations concerning all kinds of chemical terminology. Some of these names date from antiquity, while others are quite new. ![]() Names and SymbolsĮach element has a name. Their role is central to chemistry, for they combine to form the millions and millions of known compounds. An element is a substance that cannot be broken down into simpler chemical substances. ![]() The chemical alphabet consists of the 118 elements on the periodic table that have been discovered so far. However, the chemical alphabet is larger than the one we use for spelling. Just as a language has an alphabet from which words are built, chemistry has an alphabet from which matter is described.
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