Iodine has been heated and vaporizes into a purple vapor. The vapor then condenses on a 'cold finger' consisting of a test tube packed with an ice-salt mixture, and deposits as glittering black crystals.
Examples of separating mixtures: a reaction mixture (red) is being distilled to remove ethanol solvent, which condenses in the beaker to the right as a clear liquid. You can also see thin-layer chromatography plates at lower center, showing reaction progress from samples taken. Today we do our experiments on video, but someday students will be back in person.
A sample of the compound 'rubrocurcumin', synthesized from boric acid, curcumin tumeric extract, and oxalic acid in boiling acetone as an Honors Chemistry II activity. I was interested in the color: some references claimed it was red, while others claimed it was green. It turns out it's both! Depends on the angle of the light! It transmits red light and reflects green light.