what are the 4 properties of nonmetals?
['High ionization energies.', 'High electronegativities.', 'Poor thermal conductors.', 'Poor electrical conductors.', 'Brittle solids—not malleable or ductile.', 'Little or no metallic luster.', 'Gain electrons easily.', 'Dull, not metallic-shiny, although they may be colorful.']