Write out the name for (ionic compound) Al2S3
The Correct Answer and Explanation is:
The name for the ionic compound Al₂S₃ is aluminum sulfide.
Explanation:
Ionic compounds are formed when metal atoms combine with non-metal atoms. In the case of Al₂S₃, the compound is composed of aluminum (Al), a metal, and sulfur (S), a non-metal. The process of naming ionic compounds follows a systematic approach based on the charges of the ions involved.
- Aluminum (Al) is a metal from Group 13 of the periodic table. It typically forms a +3 charge when it becomes an ion (Al³⁺). The charge on aluminum ions is fixed, so there is no need to specify the charge in the name.
- Sulfur (S), a non-metal from Group 16, forms an ions with a -2 charge (S²⁻). Like aluminum, the charge on sulfur is fixed.
In ionic compounds, the total charge must balance out to zero, meaning the positive and negative charges must cancel each other out. In the case of Al₂S₃, there are two aluminum ions (each with a +3 charge) and three sulfide ions (each with a -2 charge).
- The total positive charge from the aluminum ions is: 2 × +3 = +6.
- The total negative charge from the sulfur ions is: 3 × -2 = -6.
Since the total positive charge (+6) and the total negative charge (-6) balance each other out, the compound is neutral overall.
Naming:
- The metal (aluminum) retains its elemental name.
- The non-metal (sulfur) is modified to end in -ide, thus becoming sulfide.
- The ratio of ions is determined by the need for charge neutrality. Since two aluminum ions combine with three sulfur ions to balance the charges, the formula is Al₂S₃.
Thus, the name of Al₂S₃ is aluminum sulfide.