# Question #2cb8f

Dec 23, 2015

Consider the size of the hydrogen bound atom: oxygen/nitrogen versus chlorine versus iodine. Because iodine is largest, there should be least overlap with the small hydrogen atom.

#### Explanation:

Thermodynamically, the $H - X$ bond in hydrogen iodide is the weakest bond. There is better overlap between hydrogen and the smaller atoms, and, therefore, the hydrogen element bonds resist reduction.