What is the name of the following ionic compound SnSe
2
?
The Correct Answer and Explanation is :
The ionic compound SnSe₂ is called tin(IV) selenide. To understand this name, let’s break down its components.
Composition
- Tin (Sn): This is the metal cation in the compound. Tin can have multiple oxidation states, commonly +2 and +4. In SnSe₂, it has a +4 oxidation state, which is indicated in the name by the Roman numeral IV.
- Selenium (Se): This is the nonmetal anion. In this compound, selenium is in the form of selenide, which carries a -2 charge.
Formulation
The formula SnSe₂ indicates that there are two selenium anions for every tin cation. To achieve electrical neutrality in an ionic compound, the total positive charge from the cations must balance the total negative charge from the anions. In SnSe₂, the +4 charge from one Sn⁴⁺ ion is balanced by the -4 charge from two Se²⁻ ions (2 × -2 = -4). This balance confirms that the formula is correct.
Naming Conventions
The IUPAC (International Union of Pure and Applied Chemistry) naming conventions dictate that the metal cation is named first, followed by the anion. For metals with more than one oxidation state, the oxidation state is specified in parentheses using Roman numerals. In this case, “tin” is followed by “(IV)” to indicate the +4 oxidation state. The anion, derived from selenium, is named “selenide,” which is standard for anions formed from nonmetals.
Applications
Tin(IV) selenide is of interest in various applications, including materials science and electronics. It has been studied for its potential use in thin-film solar cells, semiconductors, and other electronic devices due to its unique electrical and optical properties.
In summary, SnSe₂ is named tin(IV) selenide due to its composition and the oxidation states of its constituent elements, adhering to IUPAC naming conventions.