[BROe]

I recently planned an experiment where I convert my stock of CuCO₃ into CuCl₂ using HCl. I first did this on a smaller scale using only 5g of CuCO₃, the experiment was a success and now the next step is to extract the salt from the water, it is currently dissolved in ≈160mL of water. In order to extract it I plan to boil the solution down to a point where I could place it, now saturated, into an ice bath and decant off the water once the temp is low enough. While I expect this to work fine for the small scale experiment, in the past I have had problems where, when boiling a solution, salt will accumulate at the bottom of the flask and periodically shoot out. Is there any way to avoid this?

EDIT: I apologize for posting this after the fact but I didn't have time to include this in my original post, but as a result of the above reaction I seem to have what looks like a copper deposit on my metal stirring stick, I suspect suspending it in an acid should remove the deposit but I am uncertain. Any suggestions as to how to remove this would be appreciated.

[Arkcon]

You goal should be to stop heating before the solid begins to precipitate, and to always heat very gently to avoid bumping either solution or solution plus solid.  The ice cold bath (assuming you're using pyrex or other tempered glassware to avoid it cracking) should precipitate a fine batch of crystals.  Another trick is to put boiling stone, or better, since you want clean product, glass beads or glass chips (careful if you have to make your own in that case.)  If you're using a flask after scale up, you may have less chance of it jumping out at the end of heating in any case.

[Borek]

boiling stone

While worth a try, I am not sure it will work when the problem is with salt forming on the bottom of the flask, isolating heat source from the solution.

Solubility of CuCl₂ changes only slightly with temperature (around 41 g/100 g water at 0°C and around 51 g/100 g at 100°C, masses given for the anhydrous salt).