What term describes a category of elements that are generally good conductors of heat and electricity?

The term that describes a category of elements that are generally good conductors of heat and electricity is metals. Metals possess unique properties such as high electrical and thermal conductivity due to their structure, which includes a sea of delocalized electrons that can move freely throughout the metallic lattice. This allows metals to efficiently transfer energy in the form of heat and electric current.

In contrast, non-metals typically do not conduct electricity or heat well. They are characterized by their lack of metallic luster and are often insulating in nature. Alloys are mixtures of two or more metals (or a metal and another element) designed to enhance specific properties, but they still fundamentally rely on the properties of the metal components. Composite materials are made by combining two or more distinct substances to achieve varying properties, and their conductivity can vary widely depending on their composition. Thus, metals stand out as the primary category known for their excellent conductivity properties.