Which of the following represents the hydrogen ion component of sulfite?

The correct choice represents the hydrogen ion component of sulfite because it includes both the sulfite anion and an additional hydrogen ion, making it a bisulfite ion. The sulfite ion itself, indicated by the second option, has a charge of 2- and does not contain a hydrogen ion, which distinguishes it from the bisulfite formed when a hydrogen ion is added. The presence of the hydrogen ion in the first option indicates a species that can participate in acid-base chemistry, specifically as the conjugate acid of the sulfite ion. This is why it accurately represents the hydrogen ion component of sulfite. The other choices do not contain any hydrogen ions connected to sulfite: CN- is the cyanide ion and O2^2- is a peroxide ion, neither of which has any relation to the sulfite or its hydrogenated form.