If intermolecular forces are stronger for compound X and weaker for compound Y, then the following would be true

the boiling point would be lower for Compound X
the evaporation time would be longer for Compound X
the boiling point would be higher for Compound Y
the evaporation time would be shorter for Compound X

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

ca has a crystalline lattice with positive ions (since it is a metal, metals are positively charged) and electrons flow freely in its structure since the ca atoms have a large nuclear radius so the electrons are not tightly held, therefore the electrons can flow freely since they are not being highly attracted by the nucleus. moreover, one of the properties of metals are that they are conductors of electricity, thus proving ca is the element.