Ligand adsorption of weak acid anion is maximum at a pH which is

A. Equal to pK of weak acid

B. Greater than 10 times of pK

C. Less than 10 times of pK

D. Independent of pK

Answer: Option A

Solution(By Examveda Team)

Ligand adsorption of weak acid anion is maximum at a pH that is equal to the pK of a weak acid. pK is a measure of the strength of an acid on a logarithmic scale. And pK value is given by log₁₀(1/K_a), where K_a is the acid dissociation constant.
The mode of adsorption of ligands depends on the bond polarity of the linking atoms of the ligand.