The redox reaction between iodine I2 and iodide ions I- can be represented by the following equation:I2 + 2e- 2I-This reaction involves the transfer of electrons, with iodine gaining electrons reduction and iodide ions losing electrons oxidation . The equilibrium position of this reaction can be affected by changes in pH.As the pH increases becomes more basic , the concentration of hydroxide ions OH- in the solution also increases. The presence of hydroxide ions can react with iodine to form iodide ions and hypoiodite ions OI- , as shown in the following equation:I2 + 2OH- 2I- + O2This reaction consumes iodine and produces iodide ions, which shifts the equilibrium of the original redox reaction to the right. As a result, the concentration of iodine decreases, and the concentration of iodide ions increases.In summary, increasing the pH of the solution shifts the equilibrium position of the redox reaction between iodine and iodide ions to the right, favoring the formation of iodide ions.