Complete this sentence: Atoms emit visible and ultraviolet light A. as electrons jump from lower energy levels to higher levels. B. as the atoms condense from a gas to a liquid. C. as electrons jump from higher energy levels to lower levels. D. as they are heated and the solid melts to form a liquid. E. as the electrons move about the atom within an orbit.

Asubstance is held in an open container. its particles move past one another at random speeds but do not leave the container. heat is removed from the system, and the particles slow down. when enough heat is removed, the particles no longer have enough speed to overcome the weak attractive forces between them. when this happens, the substance enters its solid state. the process described above is known as .