Single-or Multiple-Word Names

A troublesome point in naming chemical compounds concerns the rules governing when a compound is to be written as a single word (as methylamine) or as two or more words (as methyl chloride). To solve this problem, you must determine whether the principal or parent function is an element or a compound in its own right if it is either one, then the name is written as a single word. 

7 More on Nomenclature, Compounds Other Than Hydrocarbons 

The following examples should help to clarify the system. In each name, the part of the name that denotes the parent compound2 is italicized  

However, if the parent function cannot be construed as being a real compound, the name is correctly written as two or more words. For example, CH3CI could be named as a chloride, in which case we use two words, methyl chloride, to describe it. A chloride, or any halide, is a class of compound, not a specific compound. To identify a specific halide, the adjective that describes the halide is written as a separate word preceding the class name. Examples follow in which the class name is italicized 3 

Fletcher, 0. C. Dernner, and R. B. Fox, Nomenclature of Organic Compounds. Principles and Practice, Advances in Chemistry Series, 126, American Chemical Society, Washington, D.C., 1974. 

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