The name of the compound SO
is sodium trioxide sulfur trioxide sulfur (III) oxide sulfur (VI) oxide
The Correct Answer and Explanation is:
The correct name of the compound SO₃ is sulfur trioxide.
Explanation:
The compound SO₃ is made up of sulfur and oxygen. In naming chemical compounds, especially oxides, the rules of nomenclature for molecular (covalent) compounds are applied. These rules involve using prefixes to indicate the number of atoms of each element and the root of the element’s name.
Here’s how the name sulfur trioxide is derived:
- Element Name: The first element in the compound, sulfur, is named as it is because sulfur’s symbol is S.
- Oxide: The second part of the compound is oxide because it contains oxygen (O). The suffix -ide is used when the compound is formed from oxygen and another element.
- Prefix for the Number of Oxygen Atoms: In SO₃, there are 3 oxygen atoms. The prefix “tri-“ is used to represent the number 3. Therefore, the oxygen part becomes trioxide.
Combining these two parts, we get sulfur trioxide.
Why Not the Other Names?
- Sodium Trioxide: This would imply that sodium (Na) is present in the compound, which is not the case here.
- Sulfur (III) Oxide: This name suggests that sulfur is in the +3 oxidation state. However, sulfur in SO₃ is in the +6 oxidation state, not +3.
- Sulfur (VI) Oxide: This name is technically correct in terms of oxidation state, as sulfur is in the +6 oxidation state in SO₃. However, in the nomenclature rules for molecular compounds, we usually use simple prefixes rather than oxidation states. Hence, sulfur trioxide is more commonly used.
Thus, the correct and most commonly used name for SO₃ is sulfur trioxide.
