Copper is a metallic solid in its conventional state. As a solid, the molecules of copper occupy a stable configuration known as a crystal lattice. If the temperature is above 1,984 degrees Fahrenheit, solid copper melts and becomes a liquid. Copper becomes a gas at temperatures above 4,643 degrees Fahrenheit.
Conventional physics has three states of matter: solid, liquid and gas. At room temperature, most metals are solid, with the exception of the element mercury, which is a liquid. As the temperature rises, molecules have more energy to move around and form a liquid. At still-higher temperatures, they form a gas.