Silanols are much more acidic than the corresponding alcohols. For Et3SiOH, the pKa is estimated at 13.6 vs. 19 for tert-butyl alcohol. Because of their greater acidity, silanols can be fully deprotonated in aqueous solution, especially the arylsilanols. Deprotonation of a silanol gives an anion, which can function as a ligand used as support for catalysts.
Despite their enhanced acidity, silanols appear to be nearly as basic as alcohols.[2]