Final answer:
Phenolate is the conjugate base of phenol, a weak acid. Despite the inverse relationship between the strengths of acids and their conjugate bases, phenolate does not fully ionize in solution and is thus considered a weak base, not a strong base.
Step-by-step explanation:
Is phenolate a strong or weak base? This is the question we're addressing. While it is true that the conjugate base of a weak acid is typically stronger than the conjugate base of a strong acid, calling phenolate a 'strong base' is not accurate. The term strong base is reserved for bases that are fully ionized in solution.
These include hydroxide-containing compounds like NaOH or KOH. Phenolate, the conjugate base of phenol, is weaker in comparison to these strong bases. It is considered a weak base because it does not completely ionize in solution and its basicity is mitigated by the resonance stabilization involving the aromatic ring, which disperses negative charge and makes it less reactive towards protons.
According to the acid-base equilibrium, the reaction favors the formation of the weaker acid and base. Thus, if phenolate were a strong base, it would completely convert to its conjugate acid, phenol, in water, which is not the case.
In summary, although phenolate might be stronger than the conjugate bases of strong acids, it still does not behave as a strong base in aqueous solutions and will exist in equilibrium between the base and its conjugate acid form.