In the lab you observed some dramatic combination reaction,
one of which was that between zinc and
iodine.
–Zinc + Iodine à Zinc
iodide
When a metal (such as zinc) and non-metal (such as iodine)
combine to form a compound, the name of
the compound is derived by writing the name
of the metal first followed by the name of the non-metal whose last syllable is replaced by an –ide ending.
–Iodine
therefore becomes iodide.
Hence
the name of a compound of zinc and iodine is zinc iodide.
You
also observed a reaction between aluminum and iodine.
The
word equation for that looks like this:
–Aluminum + Iodine à Aluminum
iodide