Substance 1 Substance 2 Substance 3 Substance 4 A mixture Poor conductor of heat and electricity • Forms crystals when solid High luster Conducts electricity when dissolved in water Brittle when solid • Contains particles that cannot be seen with the naked Good conductor of heat and electricity Malleable eye • Dull appearance with no luster Ductile . Hard and brittle when solid Cannot be separated by filtration High melting and boiling points Which substance is most likely a metal element?​