Hi Gabrielle W.,
You should know by this time in your course that a mole has a certain (Avogadro's Number) number of molecules to it. Just multiply that value by 7.
I'm a little sceptical that Ca(OH)2 can be described as molecules, and you should be too -- it's an ionic solid in a lattice, so not really as individual molecules as a solid, and dispersed as ions if dissolved, hence not as individual molecules there, either. If you try to vaporize it, you'll probably end up with clusters of ions or even dehydrate to CaO.
I'm not saying that it's a useless material, for all that -- great for dissolving bodies, bones and all, hence a useful ingredient in creepy murder mystery literature.
But for ordinary uses, CaCO3 is more common -- marking athletic field lines on grass, cross-country running courses, etc.
-- Cheers, -- Mr. d.