What is the chemical name of this compound? Na2S:
The correct answer and explanation is:
The chemical name of the compound Na₂S is sodium sulfide.
Explanation:
Na₂S is an ionic compound composed of sodium (Na) and sulfur (S). Sodium is a metal in Group 1 of the periodic table, known as an alkali metal. Sulfur is a nonmetal in Group 16, often called a chalcogen. In ionic compounds, metals typically form positive ions called cations, while nonmetals form negative ions called anions.
Sodium atoms lose one electron each to achieve a stable electron configuration, forming Na⁺ ions. Since sulfur needs two electrons to complete its outer shell, it gains two electrons, forming the sulfide ion S²⁻. To balance the charges, two Na⁺ ions combine with one S²⁻ ion, resulting in the formula Na₂S.
The name “sodium sulfide” comes from naming the cation first, followed by the anion. The cation is simply named after the metal, sodium. The anion name is derived from the element sulfur, modified to end with “-ide” to indicate it is a negatively charged ion, making it “sulfide.” Thus, the compound is called sodium sulfide.
Sodium sulfide is a solid crystalline compound that is highly soluble in water. It has applications in industries such as leather processing, paper manufacturing, and water treatment. The compound typically appears as yellowish crystals and can release a characteristic rotten egg smell upon contact with acids due to the release of hydrogen sulfide gas (H₂S).
Understanding the chemical naming conventions helps identify compounds accurately. For binary ionic compounds involving metals and nonmetals, the metal name remains unchanged, and the nonmetal is named by adding “-ide” to the root name. This rule applies to Na₂S, confirming the correct chemical name as sodium sulfide.