What is the IUPAC name of HI?
The correct answer and explanation is:
The IUPAC name of HI is hydroiodic acid.
Hydroiodic acid is a binary acid composed of hydrogen and iodine. The naming convention for binary acids follows a systematic approach. The first part of the name is derived from the element that is not hydrogen, in this case, iodine. The suffix “ide” is added to the element name, resulting in “iodide.” The prefix “hydro-” is added to indicate that the acid is derived from hydrogen, and the word “acid” is appended at the end to specify that it is an acid.
The general format for naming binary acids is:
- Hydro- + [name of the non-metal] + -ic acid
In this case:
- The non-metal is iodine.
- The suffix “ide” changes to “ic” when the acid is named.
- Therefore, the name becomes hydroiodic acid.
Hydroiodic acid is a strong acid, meaning it dissociates completely in water to form hydronium ions (H₃O⁺) and iodide ions (I⁻). This complete dissociation is a key feature of binary acids, and hydroiodic acid behaves similarly to other binary acids such as hydrochloric acid (HCl) and hydrobromic acid (HBr).
The strength of hydroiodic acid is attributed to the bond between hydrogen and iodine. Iodine is a large atom, and the bond between iodine and hydrogen is relatively weak, making it easy to dissociate. This contributes to its strong acidic behavior.
Hydroiodic acid is used in various chemical reactions, including in organic synthesis, and plays an important role in the preparation of iodide salts. It is also used in laboratories for different analytical applications.