Solution to Exercise 7-2-7
- Page ID
- 43262
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Phenol has a pKa of about 10, so the Henderson-Hasselbalch equation tells us that at pH 2 and 7, it will be protonated, and thus uncharged and insoluble in the buffer (phenol is quite nonpolar). At pH 12 it will be ionized (to the phenolate ion) and thus soluble (recall that ions are usually very water soluble due to strong ion-dipole interactions between solute and solvent).