Redox Titration Reaction

1207 Words5 Pages
Iodometry is a common example of redox titration reaction, involving a series of steps used to quantitatively determine the amount of oxidising agent required. The reaction mainly oxidises iodide (I-) to iodine (I2) and is a reversible process. Oxidising agent such as Copper (II) Sulfate (CuSO4) is added to react with Potassium Iodide (KI) to yield I2. Excess KI is required to get triiodide ion (I3-), which is very water-soluble, compared to I2, which is sparingly water-soluble. This step mainly retain iodine in the solution. The process of promptly titrating Sodium thiosulfate (Na2S2O3), a reducing agent, to reduce I2 back to I- is known as the iodometric titration. Iodide ions may get oxidised by the atmosphere if the titration
…show more content…
Iodometry is an indirect titration comprising of two redox reactions. The oxidising agent reacts with excess iodide to bring forth a solution of iodine which is then titrated with the titrant, standard solution of sodium thiosulfate. On the other hand, iodimetry is a direct one-step redox titration. The reducing agent is directly titrated with a standard iodine solution which serves as the titrant. Therefore, iodine is first oxidised then reduced in iodometry and only reduced in iodimetry. In addition, iodimetry is used less frequently as compared to…show more content…
This validates that iodometric titration can be used to determine the amount of oxidising agent present in the solution. However, this method in the determination of oxidising agents may not be practical in certain situations. Reason being, many reagents and steps are required to conduct the experiment. This may be limited by the lack of access to the appropriate reagents and the inability to get hold of trained personnel to conduct the experiment as titration have to be fast right after the addition of KI. Redox iodometric titration utilise the transfer of electrons and many compounds get reduced and oxidized as the experiment proceeds which forms a variety of new compounds. In turn, there is a diversity of colour change throughout the
Open Document