Question

select the correct answer.
what is the formula of sulfurous acid?
a. h₂s
b. hso₄
c. h₂so₄
d. h₂so₃

Explanation:

To determine the formula of sulfurous acid, we recall chemical naming conventions. Sulfurous acid is related to the sulfite ion (\(SO_3^{2-}\)). Acids are formed by combining \(H^+\) ions with the anion. For the sulfite ion (\(SO_3^{2-}\)), we need two \(H^+\) ions (since each \(H^+\) has a +1 charge and the anion has a -2 charge) to balance the charge. So the formula is \(H_2SO_3\). Let's check the options:

• Option A (\(H_2S\)) is hydrogen sulfide (hydrosulfuric acid), not sulfurous acid.
• Option B (\(HSO_4\)) is not a valid formula for sulfurous acid (and \(HSO_4^-\) is the bisulfate ion, related to sulfuric acid).
• Option C (\(H_2SO_4\)) is sulfuric acid, not sulfurous acid.
• Option D (\(H_2SO_3\)) matches the formula for sulfurous acid.

Answer:

D. \(H_2SO_3\)