 One of the simplest phenyl-containing compounds is phenol, C6H5OH.It is often said the resonance stability of phenol makes it a stronger acid than that of aliphatic alcohols such as ethanol (p"K"a = 10 vs. 16–18).However, a significant contribution is the greater electronegativity of the "sp"2 alpha carbon in phenol compared to the "sp"3 alpha carbon in aliphatic alcohols.