Final answer:
To determine the pH and fraction of dissociation for a 0.150 M solution of phenol, one would calculate the dissociation using an ICE table and Ka value, then find pH by taking the negative log of the hydrogen ion concentration. The fraction of dissociation is the ratio of dissociated acid to initial concentration. Factors affecting phenol's acidity include phenoxide ion stability, resonance, substituents, inductive effects, and solvent effects.
Step-by-step explanation:
To calculate the pH of a 0.150 M solution of hydroxybenzene, also known as phenol, we need to use its acid dissociation constant (Ka) which is not provided in the question. Assuming a generic weak acid, HA, the dissociation reaction is HA → H+ + A-, and the expression for the acid dissociation constant is Ka = [H+][A-]/[HA]. With the initial concentration of HA and assuming x is the concentration of H+ that dissociates, the equilibrium concentrations would be [HA] = 0.150 - x, [H+] = x, and [A-] = x.
To find the pH and fraction of dissociation of the acid solution, one might set up an ICE table and solve the quadratic equation that stems from the Ka expression, or use a simplifying assumption if valid. Once the [H+] is found, the pH can be calculated by taking the negative logarithm (base 10) of the [H+] concentration.
The fraction of dissociation (α) is the ratio of the dissociated acid concentration to the initial acid concentration, α = [A-]/[HA]initial.
Factors that influence the acidity of phenol include the stability of the phenoxide ion, resonance stabilization, substituents on the phenol ring, inductive effects, and solvent effects.