Problem 38 - Chemistry Matter and Change

Question

Write the name and formula for the compound formed from sodium ions and nitrite ions.

Step-by-Step Solution

Answer

The compound is sodium nitrite with the formula \( \text{NaNO}_2 \).

Step 1: Identify the Ions

Identify the ions involved in the formation of the compound. Sodium ions are represented as \( \text{Na}^+ \) and nitrite ions are represented as \( \text{NO}_2^- \).

Step 2: Determine the Formula

To form a neutral compound, the total charge must equal zero. Since sodium ions have a charge of \(+1\) and nitrite ions have a charge of \(-1\), one of each ion is needed to balance the charges. Therefore, the formula for the compound is \( \text{NaNO}_2 \).

Step 3: Name the Compound

In naming, the cation (sodium) is written first followed by the anion (nitrite). Therefore, the name of the compound is sodium nitrite.

Key Concepts

Understanding Sodium Ions

Sodium ions are crucial in forming many ionic compounds. Each sodium ion is represented by the chemical symbol \( \text{Na}^+ \). The plus sign indicates that a sodium atom has lost one electron, resulting in a positive charge. Sodium, a member of the alkali metals group in the periodic table, is highly reactive and tends to lose its outer electron easily. This characteristic makes sodium ions very stable and prevalent in ionic bonds. In the presence of negatively charged ions, sodium ions help in forming stable compounds. These characteristics make sodium ions indispensable in countless chemical reactions and compounds.

Exploring Nitrite Ions

Nitrite ions are represented by the formula \( \text{NO}_2^- \). The negative sign in the formula indicates that the nitrite ion carries a negative charge. Nitrite ions are composed of one nitrogen atom bonded with two oxygen atoms. This ion is part of the nitrogen compound group and displays resonance, where electrons are shared among different atoms to provide extra stability. The charge results from gaining electrons, which balances out with positively charged ions like sodium ions to create neutral compounds. Understanding the properties and behaviors of nitrite ions is key in grasping their role in forming many ionic compounds.

Crafting a Chemical Formula

Creating a chemical formula requires understanding the balance of charges between ions. For the compound formed by sodium and nitrite ions, we start by noting the individual charges: sodium ions \( (\text{Na}^+) \) and nitrite ions \( (\text{NO}_2^-) \). In ionic compounds, the goal is to achieve a neutral charge. This means the positive and negative charges must cancel each other out. Here, a single sodium ion balances with a single nitrite ion, resulting in the formula \( \text{NaNO}_2 \). This basic method is a cornerstone of chemistry, emphasizing the principle of charge balance in compounds.

Naming Ionic Compounds

The naming of ionic compounds follows a systematic approach dictated by IUPAC standards. The name usually reflects the ions involved—starting with the cation and followed by the anion. For our compound, the sodium ion \( (\text{Na}^+) \) is named first. Then, the anion nitrite \( (\text{NO}_2^-) \) follows. Thus, the complete name of the compound is sodium nitrite. This approach ensures clarity and consistency in chemical nomenclature, making it easier to identify the components of any given compound. Understanding this naming system is crucial for students learning about chemical compounds.