# What is the name of the compound "SI"_6"?

The name of the compound $\text{SI"_6}$ is sulfur hexiodide.
Since sulfur and iodine are nonmetals, this is a binary molecular compound. A binary molecular compound is named so that its subscript numbers are indicated as Greek prefixes in its name. However, if the first element has a subscript of 1 (understood), the prefix mono - is not used. The name of the second element in the compound loses one or two syllables, and it ends with the suffix $\left(\text{-ide}\right)$. The compound $\text{SI"_6}$ is named sulfur hexiodide, as the prefix for $6$ is hexa -, and the name for iodine is changed to iodide.