Which of the following correctly describes the Lewis dot structure for the ion H3S+?

• A. Sulfur is at the center, bonded to three hydrogen atoms, with no lone pairs on sulfur and a positive formal charge.
• B. Sulfur is at the center, bonded to two hydrogen atoms, with two lone pairs on sulfur and a positive formal charge.
• C. Sulfur is at the center, bonded to four hydrogen atoms, with no lone pairs on sulfur and a positive formal charge.
• D. Sulfur is at the center, bonded to three hydrogen atoms, with one lone pair on sulfur and a negative formal charge.

Answer: (A)

Verified step by step guidance

1. Identify the central atom in the ion H3S+. Since sulfur (S) is less electronegative than hydrogen (H), sulfur will be the central atom bonded to the hydrogen atoms.
2. Determine the total number of valence electrons available. Sulfur has 6 valence electrons, each hydrogen has 1 valence electron, and since the ion has a positive charge (+1), subtract one electron from the total count.
3. Distribute the electrons to form bonds between sulfur and the three hydrogen atoms. Each S-H bond consists of 2 electrons, so 3 bonds use 6 electrons.
4. Assign the remaining electrons as lone pairs on sulfur. After bonding, check how many electrons remain and place them as lone pairs on sulfur if any are left.
5. Calculate the formal charge on sulfur to ensure the structure matches the ion's charge. Use the formula: Formal charge = (Valence electrons of atom) - (Nonbonding electrons) - (Bonding electrons / 2). Confirm that sulfur has a positive formal charge and no lone pairs, consistent with the correct Lewis structure.