Types of solids

Solids are broadly divided into two types depending on how their constituent particles are arranged: crystalline solids and amorphous solids. In a crystalline solid the particles are arranged in a highly ordered, regularly repeating pattern that extends over a long range throughout the entire sample -- ice, common salt (NaCl), and metals such as sodium, gold and copper are everyday examples, along with materials like diamond, graphite and ceramics. In an amorphous solid, by contrast, the particles are arranged randomly with at most a short-range order, much like a 'frozen' snapshot of a liquid -- glass, plastic, rubber, tar and metallic glass (a metal-metalloid alloy) are common examples. The two sections that follow look at the distinguishing properties of e …