Crystal Growing

Crystal growing made easy I. Microcrystals while u wait The idea of this is to grow crystals of coloured metal compounds in drops of water on glass slides, under a biological microscope. A drop of water will completely dry up and crystallize in 30 minutes, so if you start 'em 15 minutes before class, students can observe the progress of crystal growth They don't quite grow visibly, but almost: have the students check them every 2 minutes or …

…characteristic crystal form Size doesn't matter: form does. Get the students to sketch the various crystals that they grow. Another easy couple are salt and sugar, which can be viewed under a stereoscopic mike. Salt forms little cubes, while sugar crystals are less symmetrical, with less right angles between faces. The reason for the one compound-one form rule is because of the way the atoms arrange themselves, which is characteristic of the compound in question.