Questions tagged [recrystallization]
For questions related to dissolving and subsequently precipitating as substance. The purpose may be for purifying, creating polymorphs, or other reasons.
16
questions with no upvoted or accepted answers
4
votes
0
answers
434
views
How can should one separate and purify benzophenone from salicylic acid?
I am working with two solids and I know that they are benzophenone (s)(ketone) and salicylic acid (s) (carboxylic acid). I am curious to know what is/are the best method of extraction and ...
- 71
2
votes
0
answers
169
views
Drying sodium tetraborate for use as a standard
I am currently attempting to purify technical grade sodium tetraborate decahydrate by recrystallization for use as a titration standard. I don't have a requirement for a specific grade or purity. I'm ...
- 148
2
votes
0
answers
334
views
Could you form quartz crystals by melting and cooling sand very slowly?
Since glass is amorphous quartz and when you slow the cooling of something enough it will crystallize, couldn’t you melt $\ce{SiO2}$ (sand) and then very slowly cool it to cause spontaneous nucleation ...
- 21
2
votes
0
answers
391
views
What determines the maximum size of salt crystals as grown in flux growth?
Like many other children, I grew single crystal salt crystals in a salt solution. This is a common and fun experiment for children.
However, with both this experiment, and with flux growth methods ...
- 278
2
votes
0
answers
107
views
What do DNA crystals look like?
I had about 5 ug DNA suspended in water, which I dried thoroughly in a vacufuge.
I obtained a whitish crystal (very similar to table salt, although the structure seems uneven and it's hard to tell) ...
- 597
1
vote
0
answers
15
views
Thermoplastics crystallization during nonisothermal cooling cycles
I have tested a PAEK family polymer using differential scanning calorimetry (DSC) with heating-cooling-heating cycles under different cooling rates (heating rates remained unchanged). PAEK are semi-...
- 11
1
vote
0
answers
62
views
Why isn't my sodium acetate demo working?
So I'm trying to do the sodium acetate tower demonstration that I've seen a ton of videos on. I don't have sodium acetate and I am making it from a liter of 5% distilled white vinegar and pure baking ...
- 11
1
vote
0
answers
24
views
Which ionic radius is most relevant for anticipating co-crystalization?
In the context of anticipating the likeliness that elemental impurities co-crystalize into the crystals containing an element of similar radius (see this question), which is the relevant radii to ...
- 1,077
1
vote
0
answers
51
views
Anhydrous Chromium Alum production
I recently started a small project of making home-made chromium alum crystals, as can be found on many sites, videos and recipes all around the internet.
I tried calculating the amount of salt I ...
- 379
1
vote
0
answers
42
views
Readings about chiral resolutions at the undergraduate level
Does anyone know of a resource which clearly explains the scientific theory and experimental methods involved in chiral resolutions?
I have access to the American Chemical Society, Tetrahedron, ...
1
vote
0
answers
348
views
Multi-solvent recrystallization to extract solute from glycerol?
I have compound A contaminated with impurity B. Recrystallization in water would not yield pure compound A since impurity B is less soluble in it. The only solvent in which substances A and B have ...
- 111
1
vote
0
answers
62
views
Pressure/ vacuum on preciptation of a borax saturated solution
Trying to go back to my collage chem/physics. We put a supersaturated solution of borax on the stove. (heated water, added borax till it would not take more borax). Placed them under vacuum 15 inhg,...
- 11
1
vote
0
answers
56
views
Non-destructive solvents for cyan-salts
What dissolves cyan-salts (NaCN and KCN) without destroying them the way water does via hydrolysis?
I have to make my own cyan-salts, so they're somewhat precious to me. Every time I have to ...
- 3,290
0
votes
0
answers
78
views
Can cooling rate affect the yield of crystals?
Cooling an acetanilide mixture with an ice bath has resulted to a heavier amount of acetanilide crystals than cooling the container slowly (setting it aside in the lab). I have gotten different ...
0
votes
0
answers
105
views
Why does cobalt(II) chloride (CoCl2) crystal melts?
I made $\ce{CoCl2}$ crystals by making a concentrated solution. After the crystals formed I took them out of the solution for drying.
After a time I noticed that they were still wet so I dried off ...
-1
votes
1
answer
1k
views
How does recrystallization work to purify if compounds have equal solubilities, but one is present in a greater quantity?
Every article or text I've read on crystallization states that it works by taking advantage primarily of differences in solubilities, but I've also been told that it can purify compounds with ...
- 11