Which of the following best describes HClO_4?

• A. It is an ionic compound and is named as a base.
• B. It is a molecular compound and is named as an acid.
• C. It is a molecular compound and is named using prefixes.
• D. It is an ionic compound and is named using ionic nomenclature.

Answer: (B)

Verified step by step guidance

1. Identify the chemical formula given: HClO_4, which is perchloric acid.
2. Determine the type of compound: HClO_4 consists of hydrogen (H), chlorine (Cl), and oxygen (O) atoms bonded covalently, so it is a molecular compound rather than ionic.
3. Recognize the role of hydrogen in this compound: Since hydrogen is bonded to a polyatomic ion (ClO_4^-), it can release H^+ ions in solution, making it an acid.
4. Understand the naming convention: Molecular compounds that release H^+ ions in aqueous solution are named as acids, often using the suffix '-ic' for oxyacids like perchloric acid.
5. Conclude that HClO_4 is a molecular compound named as an acid, not an ionic compound or named with prefixes.