Question

Name the following binary molecular compounds: (a) \(\mathrm{NCl}_{3}\) (b) \(\mathrm{IF}_{7}\) (c) \(\mathrm{P}_{4} \mathrm{O}_{6}\) (d) \(\mathrm{S}_{2} \mathrm{Cl}_{2}\)

Short answer

(a) Nitrogen trichloride (b) Iodine heptafluoride (c) Tetraphosphorus hexaoxide (d) Disulfur dichloride.

Step-by-step solution

Review the Naming Rules

The naming of binary molecular compounds involves using prefixes to denote the number of atoms. The prefix 'mono-' is often omitted for the first element. The second element's name is modified to end in '-ide.' Common prefixes include 'mono-' for 1, 'di-' for 2, 'tri-' for 3, 'tetra-' for 4, 'penta-' for 5, 'hexa-' for 6, 'hepta-' for 7, 'octa-' for 8, 'nona-' for 9, and 'deca-' for 10.

Naming \\(\mathrm{NCl}_{3}\\)

The compound consists of nitrogen and chlorine. Since there is one nitrogen atom, we begin with 'nitrogen.' Chlorine has three atoms, so we use the prefix 'tri-' and change the ending to '-ide,' forming 'trichloride.' Thus, the compound's name is 'nitrogen trichloride.'

Naming \\(\mathrm{IF}_{7}\\)

Here we have iodine and fluorine. With one iodine atom, we start with 'iodine.' Fluorine has seven atoms, so we use the prefix 'hepta-' and form 'heptafluoride.' Therefore, the compound is named 'iodine heptafluoride.'

Naming \\(\mathrm{P}_{4} \, \mathrm{O}_{6}\\)

The compound consists of phosphorus and oxygen. The four phosphorus atoms give us 'tetraphosphorus,' and with six oxygen atoms, we use 'hexa-' to form 'hexaoxide.' This compound's name is 'tetraphosphorus hexaoxide.'

Naming \\(\mathrm{S}_{2} \, \mathrm{Cl}_{2}\\)

This involves sulfur and chlorine. There are two sulfur atoms, so we start with 'disulfur,' and with two chlorine atoms, we say 'dichloride.' Therefore, the name is 'disulfur dichloride.'

Key concepts

Chemical Nomenclature

Chemical nomenclature is a system used by chemists to name chemical compounds in a structured way. The conventions for this system ensure that a compound's name reflects its composition.
In chemical nomenclature, there are specific rules and guidelines for naming different types of compounds. These rules ensure both clarity and consistency in communication within the field of chemistry.
For binary molecular compounds, which consist of two different non-metals, the name usually includes prefixes to convey the number of atoms. The challenge in chemical nomenclature arises because different types of compounds follow different naming conventions. These conventions help avoid ambiguities and specify the particular chemical species being discussed.

Prefixes in Chemistry

Prefixes in chemistry are used to indicate the number of atoms of each element within a compound. These are essential for understanding the composition of molecular compounds.
Some common prefixes include:

• Mono- (1) - Often omitted for the first element
• Di- (2)
• Tri- (3)
• Tetra- (4)
• Penta- (5)
• Hexa- (6)
• Hepta- (7)
• Octa- (8)
• Nona- (9)
• Deca- (10)

Prefixes make it immediately clear how many atoms of each element are present, helping to prevent misunderstandings. They are incredibly useful in specifying the exact nature of compounds during naming.

Naming Rules

Naming rules for binary molecular compounds involve several key steps that simplify the naming process. Each rule helps translate a chemical formula into an accurate: compound name.
Here are the essential steps:

• Identify the elements in the compound.
• Use a prefix to denote the number of atoms for each element; for the first element, 'mono-' is usually omitted.
• Write the name of the first element as is.
• For the second element, use an appropriate prefix, and change the ending to '-ide.'

These rules not only make naming a compound simple but also help in understanding its composition just by looking at its name. For example, \(\mathrm{NCl}_{3}\) becomes 'nitrogen trichloride,' clearly indicating one nitrogen and three chlorine atoms.

Molecular Compounds

Molecular compounds, also known as covalent compounds, are made up of two or more non-metals. These atoms are bonded by sharing electrons, which is different from ionic compounds where electrons are transferred from one atom to another.
Covalent bonding in molecular compounds results in the formation of molecules. Within these compounds, elements can combine in various ratios leading to a variety of possible compounds.
Naming these compounds involves understanding the number of atoms and utilizing prefixes, making it crucial for chemists to recognize both the elements present and their specific quantities. Knowing these basic concepts helps ensure precise communication in scientific fields.