Question

Nitrogen and oxygen form numerous binary compounds, including $\mathrm{NO}$, ${\mathrm{NO}}_2,{\mathrm{N}}_2{\mathrm{O}}_4,{\mathrm{N}}_2{\mathrm{O}}_5,$ and ${\mathrm{N}}_2\mathrm{O}$. Give the name of each of these oxides of nitrogen.

Short answer

The names of the given nitrogen-oxygen binary compounds are: 1. $\mathrm{NO}$: Nitrogen monoxide (Nitric oxide) 2. ${\mathrm{NO}}_2$: Nitrogen dioxide 3. ${\mathrm{N}}_2{\mathrm{O}}_4$: Dinitrogen tetroxide 4. ${\mathrm{N}}_2{\mathrm{O}}_5$: Dinitrogen pentoxide 5. ${\mathrm{N}}_2\mathrm{O}$: Dinitrogen monoxide (Nitrous oxide)

Step-by-step solution

Determine the oxidation numbers

To name these compounds, we first need to determine the oxidation numbers for nitrogen. 1. In $\mathrm{NO}$, nitrogen has an oxidation number of +2 and oxygen has an oxidation number of -2. 2. In ${\mathrm{NO}}_2$, nitrogen has an oxidation number of +4 and oxygen has an oxidation number of -2. 3. In ${\mathrm{N}}_2{\mathrm{O}}_4$, nitrogen has an oxidation number of +4 and oxygen has an oxidation number of -2. 4. In ${\mathrm{N}}_2{\mathrm{O}}_5$, nitrogen has an oxidation number of +5 and oxygen has an oxidation number of -2. 5. In ${\mathrm{N}}_2\mathrm{O}$, nitrogen has an oxidation number of +1 and oxygen has an oxidation number of -2.

Name the compounds

With the oxidation numbers in hand, we now provide the names for each compound: 1. $\mathrm{NO}$: Nitrogen monoxide (commonly called Nitric oxide) 2. ${\mathrm{NO}}_2$: Nitrogen dioxide 3. ${\mathrm{N}}_2{\mathrm{O}}_4$: Dinitrogen tetroxide 4. ${\mathrm{N}}_2{\mathrm{O}}_5$: Dinitrogen pentoxide 5. ${\mathrm{N}}_2\mathrm{O}$: Dinitrogen monoxide (commonly called Nitrous oxide or laughing gas)

Key concepts

Oxidation Numbers: The Basics

Understanding oxidation numbers is crucial for naming and understanding the behavior of compounds. An oxidation number is a concept in chemistry that indicates the degree of oxidation of an atom in a compound. It is essentially a bookkeeping tool to keep track of electrons in chemical reactions and compounds.
- Oxidation numbers are assigned according to a set of rules. Typically, the more electronegative element is assigned an oxidation number that reflects its nature to gain electrons. For example, oxygen usually has an oxidation number of -2 because it tends to attract electrons towards itself.
- Positive oxidation numbers often appear for less electronegative elements. For example, nitrogen might have varying positive oxidation numbers depending on the compound, such as +1 in ${\mathrm{N}}_2\mathrm{O}$ or +5 in ${\mathrm{N}}_2{\mathrm{O}}_5$.
- To find these numbers, sum the known oxidation numbers and solve for the unknown. For example, in ${\mathrm{NO}}_2$, with oxygen having an oxidation number of -2, the nitrogen must be +4 to balance out the two oxygens, giving a total charge of zero for the molecule.
This method helps deduce the composition and reactivity of compounds.

Naming Compounds: The Language of Chemistry

The ability to correctly name chemical compounds allows us to communicate precisely. The names of binary compounds, such as those formed between nitrogen and oxygen, are systematic and rely on certain conventions.
- When naming a compound, always start with the name of the first element. If the first element forms only one type of compound with the second, simple roots plus standard prefixes are used.
- Prefixes indicate the number of atoms present when needed. For example, in $\mathrm{NO}$, it is called nitrogen monoxide, denoting one atom of each element.
- Exceptions include commonly accepted names, such as calling ${\mathrm{N}}_2\mathrm{O}$ nitrous oxide or laughing gas instead of dinitrogen monoxide. Similarly, ${\mathrm{N}}_2{\mathrm{O}}_4$ is systematically named dinitrogen tetroxide because the prefix 'di-' indicates two nitrogen atoms, and 'tetra-' means four oxygen atoms.
- Consistency in the naming system allows scientists around the world to understand the chemical structure and properties of a compound just by its name.

Nitrogen Oxides: Understanding Their Nature

Nitrogen oxides are a group of compounds made up of nitrogen and oxygen. Each compound exhibits unique characteristics and plays various roles in the environment and industry.
- These oxides are formed through several natural and human activities, such as combustion processes, lightning strikes, and even biological nitrogen fixation.
- Nitric oxide ($\mathrm{NO}$) is a colorless gas known for contributing to atmospheric reactions leading to smog and acid rain.
- Nitrogen dioxide (${\mathrm{NO}}_2$) is notable for its reddish-brown color and toxic properties, often seen as pollution in urban environments.
- Dinitrogen monoxide (${\mathrm{N}}_2\mathrm{O}$), also called nitrous oxide, is unique for its use as an anesthetic "laughing gas" and its role in the greenhouse effect.
- Understanding these compounds involves recognizing their oxidation states, naming conventions, and roles in various processes, reflecting their diverse applications and implications for the environment.