Question

write the correct formula for each species: sulfur dioxide, sulfur trioxide, the sulfate ion. express your answers as chemical formulas separated by a comma.
so₂, so₃, so₄²⁻
previous answers
correct
part b
list as many similarities between these three species as you can.
check all that apply.
☑ all contain 1 sulfur atom.
□ all represent cations.
☑ all contain nonmetals only.
□ all have a charge.
☑ all contain sulfur and oxygen.
□ all represent anions.
previous answers
correct
part c
list as many differences between these three species as you can.
check all that apply.
□ so₄²⁻ is ion, so₂ and so₃ represent molecular compounds.
□ all represent ionic compounds.
□ the solubility in water differ.
□ number of oxygen atoms differ.

Explanation:

1. For the first option: $\ce{SO_4^{2-}}$ is an ion (anion), while $\ce{SO_2}$ and $\ce{SO_3}$ are molecular compounds (covalent), so this is a valid difference.
2. Second option: $\ce{SO_2}$ and $\ce{SO_3}$ are molecular (covalent) compounds, not ionic, so this is incorrect.
3. Third option: $\ce{SO_2}$, $\ce{SO_3}$, and $\ce{SO_4^{2-}}$ have different solubilities in water (e.g., $\ce{SO_2}$ and $\ce{SO_3}$ react with water, $\ce{SO_4^{2-}}$ salts have varying solubilities), so this is a valid difference.
4. Fourth option: $\ce{SO_2}$ has 2 O, $\ce{SO_3}$ has 3 O, $\ce{SO_4^{2-}}$ has 4 O, so the number of O atoms differs, which is a valid difference.

Answer:

A. $\ce{SO_4^{2-}}$ is ion, $\ce{SO_2}$ and $\ce{SO_3}$ represent molecular compounds.
C. The solubility in water differ.
D. Number of oxygen atoms differ.