Nature Study Lesson 212: Salt
"Salt dissolves in water, and as the water evaporates the salt appears in beautiful crystals."- Handbook of Nature Study, p. 753
"Let each pupil take 5 tablespoons of water and add to this about 2 tablespoons of salt, stirring the mixture until it is dissolved. When the water will take no more salt, let each pupil...lay (a square of paper in the saucer, pressing it down beneath the surface...."-HNS, p752
"'Saturated solution' is an uninspiring term to one not chemically trained; and yet it merely means water which holds as much as it can take of the dissolved substance." -HNS, p753
We have done this activity before, and these are the crystals we got within a week. but I thought I would have them do it again and compare the salt crystals.
We did two dishes this time. One we kept inside, which took about a week to appear. These crystals were smaller than our sample last time.
The other set-up was put in a sunny spot outside which only took a few days for the water to evaporate, leaving large crystals behind. This is the opposite of what we expected since the longer the crystals take to form, the larger they are supposed to be.
There must be some other factors affecting this experiment.
Any ideas?
