Chemical Forums

Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: boblalux on September 12, 2016, 04:49:07 AM

Title: Prediction of Solubility using Organic solvents
Post by: boblalux on September 12, 2016, 04:49:07 AM

Whenever I have a stain (paint, glue etc), I attempt removing it after the following scheme (if unsuccessful, I proceed to the next solvent): 
Water, soapy water, alcohol, white spirit, acetone.

My question is...
Is it possible to chemically PREDICT which solvent will be succesqsful on which material/stain?

Title: Re: Prediction of Solubility using Organic solvents
Post by: Arkcon on September 12, 2016, 05:26:19 AM

We can try, by using what we know about the stain.  However, we reach a problem immediately -- your examples aren't stains.  Paint and glue are substances that undergo chemical reactions with themselves when exposed to air and other substances.  Its almost analogous (almost but not absolutely analogous) to asking, "Can I get a solvent for just the sodium in my sodium chloride, and leave behind the chloride?"  Which is a question we do get, from time to time.

Title: Re: Prediction of Solubility using Organic solvents
Post by: boblalux on September 12, 2016, 10:08:32 AM

What I am trying to say is (forget the stain), . is it possible on the basis of knowledge of the chem formula of an organic substance to predict whether it is soluble or not in an organic solvent.

Title: Re: Prediction of Solubility using Organic solvents
Post by: Borek on September 12, 2016, 11:18:12 AM

Google for "like dissolves like". It is only a rule of thumb, but often does the trick.