I have a good understanding of solubility in gen chem, but whenever I'm given a solubility question about organic cmpds i always mess up. What are some general rules for organic cmpds solubility...like how do you determine what functional groups a compound contains based on its solubility ....
solubility rules for organic chemistry...
- Thread starter ronaldo23
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Similar polarity, ability to form extensive LDF's, h-bonds, etc.
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One thing that took me a while to figure out is that ability to hydrogen bond does NOT necessarily make something soluble in water. That is the whole principle behind extraction - something big won't be soluble in water until you remove a proton to make it charged
Also, something charged will pretty much always dissolve better than something uncharged in water, even if the uncharged thing is small and forms H bonds
Also, something charged will pretty much always dissolve better than something uncharged in water, even if the uncharged thing is small and forms H bonds
wait but why is carboxylic acid soluble in dilute base, and amine is soluble in acid. I thought for solubility it was "like dissolves like"...wouldn't -COOH be soluble in acids not bases and vice versa for -nh2?
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I'm pretty sure it's because the base will extract the proton from the carb acid and vice versa for the amine, which will allow it to undergo hydrogen bonding in an aqueos solution.
For two molecules with the same functional group (-OH, for example) the shorter R group will be more soluble.
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Acid is soluble in base because they will both ionize, leaving a carboxylate anion and -onium cation. Salts tend to be very soluble in aqueous solution (not because of H-bonding).
