As long as it's a metal, it will conduct electricity. As for heat, it will depend on which kind of metal.
In water salt dissociates into free sodium and chloride ions. Ions have charges which are able to transmit current. In plain salt the ions are bound to each other, creating neutral molecule that is...
no
No, manganese is a metallic element.
VIIB on the periodic table of the elements.
Yes it is.