In binary acid nomenclature, what is the name of the acid with the formula $HI$ (aq)?

• A. Hydrogen iodide
• B. Iodic acid
• C. Hypoiodous acid
• D. Hydroiodic acid

Answer: (D)

Verified step by step guidance

1. Identify that the compound is a binary acid because it consists of hydrogen (H) and one other nonmetal element, iodine (I).
2. Recall that binary acids are named using the prefix 'hydro-', followed by the root of the nonmetal element's name, and ending with the suffix '-ic acid'.
3. Determine the root name of iodine, which is 'iod'.
4. Combine the prefix, root, and suffix to form the acid name: 'hydro' + 'iod' + 'ic acid'.
5. Conclude that the correct name for H I (aq) is 'hydroiodic acid'.