Question

When naming a binary compound, what determines the prefix for an element in a compound?
A) The number of atoms of that element in the compound
B) The number of valence electrons in the element
C) The total number of atoms in the compound
D) The number of shared electrons in the compound
E) The number of different elements in the compound

Answer 1

Hint: Binary compounds have two elements one is nonmetal atom and another one is metal atom. Naming of compounds include the use of certain laws. Some compounds may contain atoms of more than one type and we mention each of them when naming the compound.

Complete step by step answer:
All chemical compounds have their scientific name. Apart from this there are trivial or common names for certain compounds for their easier identification.
When naming a compound, we can include prefixes or suffixes which sometimes shows the name of substituents etc. The word prefix indicates the part of the name which appears before the word root. Prefixes are used to represent the number of atoms of a particular element in that compound when we are naming a binary compound.
For example, we can take the compound \[{\text{PC}}{{\text{l}}_{\text{5}}}\]. This compound is named as phosphorus pentachloride. Here the word ‘penta’ shows the number of chlorine atoms in the compound and the prefix is added before the root word, that is, chloride. Several examples include \[{\text{S}}{{\text{F}}_{\text{4}}}\], sulphur tetrafluoride and \[{\text{PC}}{{\text{l}}_{\text{3}}}\],phosphorus trichloride etc.
From all these examples we came to know that when naming a binary compound, the prefix for an element is determined by the number of atoms of that element in the compound.

So, the correct answer is Option A.

Additional information:
The nomenclature of compounds was revised by a system called the International Union of Chemists (IUC). The system was again revised further as the International Union of Pure and Applied Chemistry (IUPAC).

Note: Naming of a compound includes the root word, suffixes and prefixes. Prefix is the part of the name added before the root word in the name. There are two types of binary compounds; they are binary ionic compounds which contain metal and nonmetal and binary molecular compounds containing both are nonmetal.