Which of the following would classify as a metal?

Aluminum is classified as a metal because it possesses characteristics typical of metallic elements. Metals are generally known for their malleability, ductility, electrical conductivity, and thermal conductivity. Aluminum, specifically, is lightweight yet strong, can be easily shaped and stretched, and is an excellent conductor of electricity. Additionally, metals, including aluminum, tend to have a shiny luster when polished.

In contrast, wood, plastic, and glass do not share these metallic properties. Wood is an organic material that is primarily used for structural and aesthetic purposes and lacks the conductive qualities of metals. Plastic is a synthetic material that is usually an insulator and is not malleable in the same way metals are. Glass, while it can be formed and shaped, is a non-metallic substance that does not conduct electricity and is typically brittle rather than ductile. Understanding these classifications is crucial for distinguishing between materials based on their physical and chemical properties.