Sciencemadness Discussion Board

Is it possible to grow crystals of insoluble salts?

fusso - 2-10-2018 at 13:07

Is it possible to grow crystals of insoluble salts, eg CaCO3 & AgCl, in a home lab?

[Edited on 02/10/18 by fusso]

happyfooddance - 2-10-2018 at 13:29

Yeah, they're called rocks
https://en.wikipedia.org/wiki/Chlorargyrite

fusso - 2-10-2018 at 15:29

Quote: Originally posted by happyfooddance  
Yeah, they're called rocks
https://en.wikipedia.org/wiki/Chlorargyrite
No, I mean growing the crystals in a home lab, not in the nature.

[Edited on 02/10/18 by fusso]

happyfooddance - 2-10-2018 at 15:36

Yes, there are many ways and there are threads on sciencemadness as well. Try searching for hydrothermal synthesis.

macckone - 2-10-2018 at 19:09

I would not try the hydrothermal synthesis of quartz at home.
It either takes too long or takes too high of a temp and pressure.

Silver chloride and marble are within the reach of a home lab.
Selenite is apparently easier than marble.

Dmishin - 5-10-2018 at 14:01

Gel growing method is way more accessible for home lab.

mayko - 5-10-2018 at 14:34

Quote: Originally posted by Dmishin  
Gel growing method is way more accessible for home lab.


There's some information on gels and gel crystallography here:
https://www.sciencemadness.org/whisper/viewthread.php?tid=75...

There's also this passage from "A Course In Inorganic Preparations", by Henderson & Fernelius, p 39, available in the forum library:

Quote:

EXERCISE 16. CRYSTALLIZED BARIUM THIOSULFATE,BaS2O2,H2O
Sometimes it is desired to obtain a small quantity of a sparingly soluble salt in well-crystallized condition rather than in the form of a fine precipitate. This may be accomplished by allowing the double decomposition to proceed slowly by diffusion.
Obtain a large beaker of at least 2 1. capacity or a battery jar or a rather deep crystallizing dish of about 25 cm. diameter, also two small crystallizing dishes (or beakers without lips) of about 75 cc. capacity (Fig.5). Fill the one small dish three fourths full with a saturated solution of sodium thiosulfate, adding some crystals of the solid salt. Similarly, add to the second dish a saturated solution and crystals of barium chloride or nitrate. Place the two dishes 3 or 4 cm. apart in the large dish and carefully fill them with water without stirring. By means of a rubber tube connected with the supply of distilled water, flow water into the large vessel to a height of at least 4 cm. above the tops of the small beakers. The whole idea is to avoid the premature mixing of the two reagents. Pour a layer of melted paraffin over the surface of the water to protect the contents of the vessel from disturbances that might produce convection currents and set the vessel away in a place where it can remain undisturbed for several weeks at as nearly constant temperature as possible. slowly, as diffusion brings the reagents into contact. When a sufficient crop has been secured, carefully remove the paraffin, siphon off the solution as well as possible, and lift out the small beakers with their contents. Collect the crystals and dry them on paper. The place where they will form will depend on the relative rates of diffusion of the two ions concerned in the precipitation.