# C6H5CO2H dimerization in Benzene

Why does $$\ce{C6H5COOH}$$ in benzene form dimers? Also why only in benzene, why not in other solvents such as water?

In general, what are the properties of compounds which form dimers or polymers in benzene?

• Hint: somehow it didn't occur to you that your asking about hydrogen bonds. Nov 1, 2015 at 16:49
• Yes, but why in benzene, and why not in water? Nov 1, 2015 at 16:54
• en.wikipedia.org/wiki/Carboxylic_acid Nov 1, 2015 at 17:02
• I see. So they will form dimers in non-polar solvents. Can you explain this please? "whereas higher carboxylic acids are less soluble due to the increasing hydrophobic nature of the alkyl chain." Thanks! Nov 1, 2015 at 17:05
• That should be an entirely separate question. However, if you bear in mind that water is a pretty polar solvent, and alkyl groups are non-polar (hydrophobic basically means non-polar), I suppose you could deduce the answer. Nov 1, 2015 at 17:09