How do metals differ from nonmetals in their physical properties?

Metals and nonmetals are distinguished by several key physical properties, reflecting their different atomic structures and behaviors.

Physical Properties of Metals

Metals are typically characterized by:
* Conductivity: They possess high electrical and thermal conductivity due to the presence of free electrons that move throughout the solid.1
* Mechanical Properties: Metals are generally malleable (can be hammered into sheets) and ductile (can be drawn into wires). These properties are often attributed to their crystalline structure, which allows for plastic deformation.1
* Lustre: They exhibit a characteristic metallic lustre, appearing opaque and highly reflective of light.12
* State: Most metals are crystalline solids with a high degree of symmetry.1

Physical Properties of Nonmetals

In contrast, nonmetals display a much wider range of physical characteristics:
* Conductivity: They act as insulators or semiconductors, having low to moderate electrical conductivity that typically increases with temperature.3
* Mechanical Properties: Nonmetals vary significantly, ranging from brittle to plastic.3
* Optical Properties: They exhibit diverse optical qualities, ranging from transparent to opaque.3
* State: Unlike metals, nonmetals can exist in solid, liquid, or gaseous states at normal temperatures and pressures.3