Question

Which bond type is soluble in alcohol?

Metallic, ionic, polar covaletn, or nonpolar covalent bonds?

Which bond type has hard, brittle crystals?

(I think the second is ionic, but not positive.)

Answer 1

Polar covalent is more likely to be soluble in alcohol. I think you are right about the ionic crystals. They are hard and cleave along planes although I don't think they are necessarily brittle per se, at least the way I define brittle.