Which of the following is the correct chemical formula for chlorous acid?

• A. HClO
• B. HClO_3
• C. HClO_2
• D. HCl

Answer: (C)

Verified step by step guidance

1. Understand that chlorous acid is an oxyacid of chlorine, where chlorine is bonded to oxygen and hydrogen.
2. Recall that the naming of oxyacids with chlorine follows a pattern based on the number of oxygen atoms: hypochlorous acid (HClO), chlorous acid (HClO_2), chloric acid (HClO_3), and perchloric acid (HClO_4).
3. Identify that the suffix '-ous' in chlorous acid indicates it has fewer oxygen atoms than chloric acid but more than hypochlorous acid.
4. Match the name 'chlorous acid' to the formula with two oxygen atoms bonded to chlorine, which is HClO_2.
5. Confirm that the correct chemical formula for chlorous acid is \(HClO_2\).