iron is a kind of solid & iron nails are made of iron ->  iron nails are solid  iron nails are solid & state of matter is a property of substance includes values of solid / liquid / gas ->  iron nails are solid in state of matter  iron is a kind of metal & iron nails are made of iron ->  iron nails are made of metal  iron nails are made of metal & a thermal energy conductor conducts heat & metal is a thermal energy conductor ->  iron nails can conduct heat  iron is always magnetic & iron nails are made of iron ->  iron nails are magnetic  iron nails are solid in state of matter & iron nails can conduct heat & iron nails are magnetic -> iron nails can conduct heat and are magnetic and are solid