Question

Compare and contrast the formulas of (a) nitride with nitrite (b) nitrite with nitrate (c) nitrous acid with nitric acid

Short answer

Nitride (N^(3-)) is a simple ion with just nitrogen, nitrite (NO2^-) and nitrate (NO3^-) are polyatomic ions differing by one oxygen atom. Nitrous acid (HNO2) relates to nitrite and has one less oxygen than nitric acid (HNO3), which relates to nitrate.

Step-by-step solution

Understanding the Ion Formulas

Start by recognizing the chemical formulas and charges for nitride (a monatomic ion), nitrite (a polyatomic ion), and nitrate (also a polyatomic ion). Nitride is represented by the symbol N with a 3- charge, shown as N^(3-). Nitrite is a polyatomic ion with the formula NO2^-, and nitrate is another polyatomic ion with the formula NO3^-.

Compare Nitride and Nitrite

Nitride (N^(3-)) is a simple anion composed of nitrogen alone with a -3 charge, whereas nitrite (NO2^-) includes both nitrogen and oxygen, specifically one nitrogen atom covalently bonded to two oxygen atoms and carries a single negative charge.

Compare Nitrite and Nitrate

Both nitrite (NO2^-) and nitrate (NO3^-) are polyatomic ions composed of nitrogen and oxygen. The difference lies in the number of oxygen atoms: nitrite has two oxygens, while nitrate has three. Additionally, both carry a single negative charge, but their structures and acid-base properties differ due to the number of oxygen atoms.

Distinguishing Nitrous Acid from Nitric Acid

Nitrous acid (HNO2) is the acid form of nitrite (NO2^-), and nitric acid (HNO3) is the acid form of nitrate (NO3^-). Specifically, nitrous acid has one hydrogen, one nitrogen, and two oxygen atoms, while nitric acid has one hydrogen, one nitrogen, and three oxygen atoms.

Key concepts

Nitride vs Nitrite

When studying chemical compounds, it's crucial to distinguish between ions that have similar names but different compositions and properties. Nitride and nitrite are two such ions that often cause confusion. Nitride is a monatomic ion with the formula N^{3-}, meaning it consists of a single nitrogen atom carrying a triple negative charge. This ion is typically formed when nitrogen gains three electrons, filling its outer shell to achieve stability.

In contrast, nitrite is a polyatomic ion, which means it is composed of more than one atom. Its chemical formula is NO_2^-, indicating that it contains one nitrogen atom covalently bonded to two oxygen atoms, and as a whole, the ion carries a single negative charge. The presence of oxygen makes a significant difference not only in the ion's composition and structure but also in how it behaves in chemical reactions.

Understanding these distinctions is fundamental for interpreting chemical equations and predicting the outcome of reactions where these ions are involved.

Nitrite vs Nitrate

Diving deeper into the realm of polyatomic ions, students encounter the pair of nitrite and nitrate, which differ subtly yet significantly. Both nitrite, with the formula NO_2^-, and nitrate, with the formula NO_3^-, include the same types of atoms – nitrogen and oxygen. However, the number of oxygen atoms is what sets them apart. Nitrite has two oxygen atoms, whereas nitrate has three.

This additional oxygen atom in the nitrate ion doesn't change the overall charge; both ions have a negative one charge. However, it alters the physical and chemical properties of the ion, including how it interacts with other substances. For example, nitrate is generally more stable and is often found in nature as a part of the nitrogen cycle, while nitrite is less stable and is a key intermediate in biochemical processes.

Understanding the structural differences between these ions is crucial, especially when dealing with their roles in environmental chemistry and biological systems.

Nitrous Acid vs Nitric Acid

Chemistry students must be familiar with the relationship between ions and their corresponding acids. Nitrous acid (HNO_2) is closely related to nitrite (NO_2^-), and nitric acid (HNO_3) corresponds to nitrate (NO_3^-). These acids can be thought of as the protonated forms of their respective ions.

Nitrous acid consists of one hydrogen atom, one nitrogen atom, and two oxygen atoms. It is a weak acid and not often encountered in its pure form because it is unstable. Instead, it is commonly found in solution or formed in situ during some chemical reactions. Nitric acid, on the other hand, contains an additional oxygen atom, making its formula HNO_3. This acid is much stronger and is a key industrial and laboratory reagent, used in various applications from fertilizers to explosives.

The additional oxygen in nitric acid contributes to its greater stability and reactivity compared to nitrous acid. These distinctions are essential for studying acid-base chemistry, and understanding them helps predict the behavior of these substances in different chemical environments.