Which of the following is the correct name for the polyatomic ion SO_3^{2-}?

• A. Sulfite
• B. Thiosulfate
• C. Sulfoxide
• D. Sulfate

Answer: (A)

Verified step by step guidance

1. Identify the chemical formula of the polyatomic ion given: \(\mathrm{SO_3^{2-}}\).
2. Recall the common naming conventions for sulfur-oxygen polyatomic ions: ions with three oxygens and a 2- charge are typically either sulfite or sulfate.
3. Understand that 'sulfate' corresponds to \(\mathrm{SO_4^{2-}}\) (with four oxygens), while 'sulfite' corresponds to \(\mathrm{SO_3^{2-}}\) (with three oxygens).
4. Recognize that 'thiosulfate' contains sulfur and oxygen but has a different formula (\(\mathrm{S_2O_3^{2-}}\)), and 'sulfoxide' is not a polyatomic ion but a functional group in organic chemistry.
5. Conclude that the correct name for \(\mathrm{SO_3^{2-}}\) is 'sulfite' based on the number of oxygen atoms and charge.