Final answer:
Metals are shiny, good conductors of electricity and heat, malleable, and ductile. Nonmetals are dull, poor conductors of electricity and heat, and brittle in solid form.
Step-by-step explanation:
The key difference between metals and nonmetals lies in their physical and chemical properties. Metals are generally shiny, silvery in color, and good conductors of electricity and heat. They are also malleable and ductile. Nonmetals, on the other hand, are dull in appearance, poor conductors of electricity and heat, and brittle in solid form.