The super saturated solution prepared last week was looked at and a small crystal of solute added to the solution. The crystal formation in the liquid occurred at once, leaving a solid in the flask. A video also was used to show the crystallization, which was quite dramatic. Definitions of solute and solvent were used to explain the process. The colors emitted by hydrogen, neon and mercury, when excited by an electric current was demonstrated and the light being emitted by the electrons dropping to a lower energy level pointed out. The science behind this will be explained in detail in the next few lessons.