Problem 58 - Chemistry and Chemical Reactivity

Question

Name each of the following binary, nonionic compounds: (a) \(\mathrm{N}_{2} \mathrm{O}_{5}\) (b) \(\mathrm{P}_{4} \mathrm{S}_{3}\) (c) \(\mathrm{OF}_{2}\) (d) \(\mathrm{XeF}_{4}\)

Step-by-Step Solution

Answer

(a) Dinitrogen Pentoxide; (b) Tetraphosphorus Trisulfide; (c) Oxygen Difluoride; (d) Xenon Tetrafluoride.

Step 1: Identify the prefixes for the number of atoms

To name binary, nonionic compounds, use prefixes to denote the number of atoms. Here are some prefixes: 'Mono' for 1, 'Di' for 2, 'Tri' for 3, 'Tetra' for 4, 'Penta' for 5, and 'Octa' for 8. These are crucial in naming each compound's chemical formula.

Step 2: Combine the prefix with the element name for each

For each compound, we use the prefix for the number of each type of atom and then combine it with the element names. The order is generally the element that is less electronegative first.

Step 3: Apply the prefixes and complete naming (a)

For \(\mathrm{N}_{2} \mathrm{O}_{5}\), 'Di-nitrogen' notices the two nitrogen atoms (‘Di’ for 2) and 'Penta-oxide' for the five oxygen atoms (‘Penta’ for 5). Thus, the name is Dinitrogen Pentoxide.

Step 4: Apply the prefixes and complete naming (b)

For \(\mathrm{P}_{4} \mathrm{S}_{3}\), 'Tetra-phosphorus' denotes four phosphorus atoms (‘Tetra’ for 4) and 'Tri-sulfide' denotes three sulfur atoms (‘Tri’ for 3). Thus, the name is Tetraphosphorus Trisulfide.

Step 5: Apply the prefixes and complete naming (c)

For \(\mathrm{OF}_{2}\), 'Oxygen' is alone so it retains its name without ‘mono’, but we use 'Di-fluoride' for the two fluorine atoms (‘Di’ for 2). Thus, the name is Oxygen Difluoride.

Step 6: Apply the prefixes and complete naming (d)

For \(\mathrm{XeF}_{4}\), 'Xenon' is alone so it retains its name without 'mono', and 'Tetra-fluoride' for the four fluorine atoms (‘Tetra’ for 4). Thus, the name is Xenon Tetrafluoride.

Key Concepts

Chemical Nomenclature

Chemical nomenclature is the systematic method of naming chemical compounds. By following specific rules and guidelines, we ensure that each compound has a unique and universally understood name. This system helps scientists and students worldwide communicate effectively when discussing complex substances. In particular, binary compounds, which consist of two different elements, are named by paying attention to the number of atoms of each element and their order within the formula. Naming clarity is crucial since miscommunication can easily occur without an agreed-upon system.
When naming binary compounds, you generally start with the less electronegative element first, followed by the more electronegative element, typically modified with a prefix and ending in '-ide.' This standard convention helps differentiate between common and uncommon compounds.

Molecular Compounds

Molecular compounds are formed when two or more non-metals share electrons, creating covalent bonds. These compounds can form complex structures but are named systematically to express their composition clearly.
For instance,

• In - (a) Dinitrogen Pentoxide, the term 'dinitrogen' signals two nitrogen atoms, while 'pentoxide' signals five oxygen atoms.
• Conversely, in - (b) Tetraphosphorus Trisulfide, 'tetraphosphorus' reflects four phosphorus atoms, and 'trisulfide' shows there are three sulfur atoms present.

Using prefixes in their names helps in distinguishing different molecular compounds, even when they share similar elemental components.

Binary Compounds

Binary compounds are chemical compounds that contain exactly two different elements. These elements can be as varied as non-metals combining to form a new substance with unique properties.
These compounds must be named accurately to reflect the number of atoms and the elements present.

• For example, - (c) Oxygen Difluoride is named to indicate that oxygen combines with two fluorine atoms.
• Similarly, - (d) Xenon Tetrafluoride appropriately notes that xenon combines with four fluorine atoms.

Recognizing these compound types allows us to predict attributes and behaviors based on their composition alone, aiding study and comprehension.

Prefixes in Chemistry

Prefixes play an essential role in the naming of chemical compounds, especially when it comes to molecular and binary compounds. These prefixes help convey the exact number of atoms from each element present within a compound.

• Some common prefixes include:
  • 'Mono-' for 1
  • 'Di-' for 2
  • 'Tri-' for 3
  • 'Tetra-' for 4
  • 'Penta-' for 5
  • 'Octa-' for 8

These prefixes ensure precision and help users properly interpret chemical formulas.
Notably, prefixes simplify even the daunting task of naming complex compounds by following a structured approach. By mastering this aspect of nomenclature, students can succinctly describe molecular structures with ease.