Question

Phenol is more acidic than:

Answer 1

Hint: Remember that the acidity of any compound is proportional to its ability to release \[{H^ + }\] ions, and the more stable the conjugate base, the stronger the acid. You can now easily answer the given question by using this.

Complete answer:
Since the phenoxide ion is more stable than the alkoxide ion, phenol is more acidic than cyclohexanol and acyclic alcohols. The negative charge in an alkoxide ion, such as the one formed from cyclohexanol, is concentrated at the oxygen atom. The negative charge in a phenoxide ion, on the other hand, is delocalized over the benzene ring and thus resonance-stabilized.
In the case of phenols, the phenols lose \[{{\text{H}}^{\text{ + }}}\] in which the negative charge on the oxygen atom is delocalized around the ring by resonance, resulting in phenoxide ions. The negative charge on oxygen is delocalized to the ortho and para carbon atoms in this way, and the phenoxide ion becomes a stable resonating structure. This makes phenol more acidic than alcohols by stabilising the phenoxide ion.
So, since it is difficult to extract the hydrogen ion from ethanol, we can assume that ethanol is less acidic than phenol, whereas phenol is more acidic than ethanol because it can quickly lose the hydrogen ion due to electron delocalization by resonance in phenols.
As phenol loses its hydrogen ion, it produces phenoxide, which is stabilised to some degree because the negative charge on the oxygen atom is delocalized across the ring, which ensures that it is shared by a number of carbon atoms in the benzene ring. As a result, the more stable the resulted ion is, the more likely it is to shape.
Furthermore, the presence of an electron withdrawing group raises the acidity of phenol by stabilising the phenoxide ion formed, while the presence of an electron releasing group lowers the acidity of phenol by destabilising the phenoxide ion formed.

Note:
It's worth noting that phenol is more acidic than water, while alcohols are more acidic than water. Dow's method is also used to produce phenol (from chlorobenzene by cumene process). Also, keep in mind that carbolic acid is a liquid solution of phenol containing approximately \[5\% \]water. When exposed to air and light, phenol turns pink.