Organic compounds are compounds with carbon atoms and are named by a separate nomenclature system. If you recall the introduction of polyatomic ions, you will remember that the bonds that hold the polyatomic ions together are covalent bonds.
Once the polyatomic ion is constructed with covalent bonds, it reacts with other substances as an ion. The bond between a polyatomic ion and another ion will be ionic. An example of this type of situation is in the compound sodium nitrate. Sodium nitrate is composed of a sodium ion and a nitrate ion. The nitrate ion is held together by covalent bonds and the nitrate ion is attached to the sodium ion by an ionic bond. 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:.
Learning Objectives Determine the name of a simple molecular compound from its chemical formula. Molecular Compounds Molecular compounds are inorganic compounds that take the form of discrete molecules. Naming Binary Molecular Compounds Recall that a molecular formula shows the number of atoms of each element that a molecule contains.
Note Generally, the less electronegative element is written first in the formula, though there are a few exceptions. The a or o at the end of a prefix is usually dropped from the name when the name of the element begins with a vowel.
Arabic alchemy has given us a number of chemical terms. Finally, in , it become a part of chemical nomenclature that denoted a common class of organic compound. The general practice among chemists is to use the more common chemical names whenever it is practical to do so, especially in spoken or informal written communication. Many, like sal ammoniac mentioned above, have fascinating stories behind their names. A system of naming that includes using Roman numerals to indicate the charge on transition metals.
The name by which a species is known to the general public, rather than its taxonomic or scientific name. Skip to content Naming Ionic Compounds An ionic compound is named first by its cation and then by its anion. The net charge of an ionic compound must be zero. Therefore, the number of cations and anions in an ionic compound must be balanced to make an electrically neutral molecule. When naming ionic compounds, the cation retains the same name as the element. Key Terms Stock system : A system of naming that includes using Roman numerals to indicate the charge on transition metals.
The Greek prefixes are used to dictate the number of a given element present in a molecular compound. Common exceptions exist for naming molecular compounds, where trivial or common names are used instead of systematic names, such as ammonia instead of nitrogen trihydride or water instead of dihydrogen monoxide. Key Terms nomenclature : A set of rules used for forming the names or terms in a particular field of arts or sciences.
A single substance can have several such names. Some common names for chemical substances have historical roots and have been used for thousands of years. Common chemical names are used in spoken or informal written communication by chemists. For some simple compounds, their systematic and common names are the same. Key Terms common name : The name by which a species is known to the general public rather than its taxonomic or scientific name.
Provided by : Boundless. Ionic compounds have high melting and boiling points, and they tend to be hard and brittle. Ions can be single atoms, as the sodium and chlorine in common table salt sodium chloride , or more complex polyatomic groups such as the carbonate in calcium carbonate. But to be considered an ion, they must carry a positive or negative charge. By sticking to each other, they resolve, or partially resolve, their separate charge imbalances.
Positive to positive and negative to negative ionic bonds do not occur. Most cations and anions can combine to form solid compounds that are usually known as salts. Its older name is cupric chloride. An ionic compound is named first by its cation and then by its anion. The cation has the same name as its element. For example, NaF is also known as sodium fluoride. If either the cation or the anion was a polyatomic ion, the polyatomic ion name is used in the name of the overall compound.
The polyatomic ion name stays the same. For example, Ca NO 3 2 is called calcium nitrate. For cations that take on multiple charges typically transition metals , the charge is written using Roman numerals in parentheses immediately following the element name.
This compound is therefore, copper II nitrate. Names of some ionic compounds : Common, or trivial, names of compounds are sometimes used in informal conversations between chemists, especially older chemists.
Systematic names are formal names that are always used in print. Since some metallic elements form cations that have different positive charges, the names of ionic compounds derived from these elements must contain some indication of the cation charge.
The older method uses the suffixes -ous and -ic to denote the lower and higher charges, respectively. This system is still used, although it has been officially supplanted by the more precise, if slightly cumbersome, Stock system. In both systems, the name of the anion ends in -ide. Molecular compounds are named using a systematic approach of prefixes to indicate the number of each element present in the compound.
The primary function of chemical nomenclature is to ensure that a spoken or written chemical name leaves no ambiguity concerning to what chemical compound the name refers. Each chemical name should refer to a single substance. Today, scientists often refer to chemicals by their common names: for example, water is not often called dihydrogen oxide.
However, it is important to be able to recognize and name all chemicals in a standardized way. Molecular compounds are made when two or more elements share electrons in a covalent bond to connect the elements. Typically, non-metals tend to share electrons, make covalent bonds, and thus, form molecular compounds. Generally, the more electropositive atom is written first, followed by the more electronegative atom with an appropriate suffix.
Organic molecules molecules made of C and H along with other elements do not follow this rule. Naming Compounds — Part 2 — YouTube : This video explains how to use a chemical name to write the formula for that compound. Acid names are based on the anion they form when dissolved in water; base names follow the rules for ionic, organic, or molecular compounds.
Acids are named by the anion they form when dissolved in water. Depending on what anion the hydrogen is attached to, acids will have different names. Simple acids, known as binary acids, have only one anion and one hydrogen.
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