Metals • shiny • malleable • ductile • good conductors of thermal and electric energy • have reactivity Metalloids Nonmetals • dull • share some properties of • brittle metals and some of nonmetals. • not malleable •some are shiny some are dull • not ductile • some are malleable and some are not • poor conductors of thermal and electric energy • some are ductile and some are not •semiconductors of electric energy • some have reactivity Malleable is the ability of a metal to be hammered into a thin sheet. Ductile is the ability of a metal to be drawn into thin wires. Conductor means an element has the ability to carry electric current or heat (thermal energy). Reactivity means an element has the ability to combine with other elements. Brittle means an element breaks easily. Shiny is the ability of an element to reflect light. Dull is not being shiny (does not reflect light.. Semiconductors carry some electric current when certain conditions are present. They can not carry heat or electric current through them.