Which best describes an alloy?

An alloy is best described as a mixture of two or more metals or a metal combined with one or more nonmetals. This is crucial in materials science and metallurgy because alloys are engineered to enhance specific properties such as strength, durability, corrosion resistance, and conductivity, which cannot be achieved through pure metals alone.

Alloys are fundamental in construction and manufacturing as they provide materials that can withstand various environmental conditions and mechanical stress. For example, steel, an alloy of iron and carbon, is significantly stronger than pure iron, making it ideal for use in construction.

The other descriptions do not accurately reflect the nature of an alloy. A compound consisting of only one type of metal would not capture the essence of what an alloy is; rather, it describes a pure substance. A pure metal, by definition, lacks the combination with other elements that defines an alloy. Lastly, characterizing an alloy as a type of plastic from natural sources is misleading, as alloys are metal-based mixtures, entirely distinct from plastics which are organic polymers.